JP4098771B2 - Wheel - Google Patents

Description

  The present invention relates to wheels employed in silver cars, forklifts, golf carts and the like.

  Conventionally, as a wheel employed in a vehicle such as a silver car, as shown in FIG. 2, a wheel 31 and a tire 33 attached to a rim 32 provided on the outer peripheral side of the wheel 31 are provided. The wheel main body 34 attached to the axle and the rim 32 provided on the outer peripheral side of the wheel main body 34 are constituted by a pair of left and right components 34L, 34R, 32L, 32R, and the wheel configuration on the same side in the left-right direction. The body 34L, 34R and the rim constituting body 32L, 32R are integrally formed of a plate material, and a folded portion 36 extending inward in the left-right direction is provided on the outer peripheral side of the left and right rim constituting bodies 32L, 32R. Engaging grooves 37 are formed on both left and right side surfaces of the tire 33, and the inner circumferential side of the tire 33 is formed by the left and right rim components 32L and 32R so that the folded portion 36 is inserted into the engaging groove 37. By sandwiching the lifting shape, there is a wheel 30 that is configured to mount the tire 33 to a wheel 31 (see Patent Document 1).

The tire 33 is mainly composed of an inner peripheral rim mounting portion 38 mounted on the rim 32 and a tire outer peripheral portion 39 protruding outward in the wheel radial direction from the rim 32, and a hollow portion 40 is formed therein. Formed over the entire circumference of the tire 33, and the rim mounting portion 38 is separated by a split surface 41 extending from the tire inner peripheral surface to the cavity portion 40, and an interval 42 is provided between the split surfaces 41 over the entire periphery of the tire 33. In addition, the left and right side surfaces 43 of the tire outer peripheral portion 39 are formed in a plane parallel to a plane orthogonal to the left-right direction.
The relationship between the distance A between the left and right folded portions 36 of the rim 32 and the distance A ′ between the bottom portions of the left and right engagement grooves 37 in a state where the split surface 41 of the rim mounting portion 38 is in close contact is expressed as A <A. In addition, the relationship between the distance B between the inner surfaces of the left and right side portions 44 of the rim 32 and the left and right width B ′ of the rim mounting portion 38 in a state where the split surface 41 of the rim mounting portion 38 is matched is B <B ', and when the rim is mounted, the left and right wheel body constituting bodies 34L and 34R are fastened by the fasteners 45 such as bolts and nuts so that the split surface 41 of the rim mounting portion 38 is in close contact with the rim. The constricted portion 46 formed by the mounting portion 38 and the engagement groove 37 is compressed by the left and right rim constituting bodies 32L and 32R so that the rim mounting portion 38 is firmly fixed.
JP 2004-122926 A

In the wheel adopted for the silver car or the like, there is a demand to widen the right and left width of the tire 33 so that the tire 33 does not fit into a relatively narrow groove or the like, as shown in FIG. Thus, when the left and right width of the tire 33 is simply widened as a whole, the left and right width B of the rim mounting portion 38 is also widened corresponding to the widening of the left and right width D of the tire outer peripheral portion 39, and the rim 32 is accordingly increased. The spacing A between the folded portions 36 is equally wide.
Thus, when the narrow tire 33 shown in FIG. 2 is simply widened as shown in FIG. 3A, the rim mounting portion 38 and the constricted portion 46 have the same dimensions as the conventional one shown in FIG. As a result of compression by (A′-A), the compression ratio of the rim mounting portion 38 and the constricted portion 46 indicated by G in FIG. 3A is greatly reduced, and the holding force of the rim 32 against the tire 33 is weak. Problem arises.

Therefore, in order not to greatly reduce the holding force of the rim 32, at least the constricted portion 46 must be compressed with a size larger than the conventional one shown in FIG. If the constricted portion 46 is compressed with a length larger than that of the conventional one shown in FIG. 2, the distortion of the tire surface in the vicinity of the engagement groove 37 increases, causing cracks and other cracks.
Further, as shown in FIG. 3B, when the lateral width F of the folded portion 36 of the rim 32 is increased and the depth of the engagement groove 37 is increased accordingly, as shown in FIG. When the sidewall portion 47 of the tire outer peripheral portion 39 is elastically deformed, the engagement groove 37 is greatly opened as indicated by a symbol H, and a problem that foreign matter is caught in the engagement groove 37 occurs.

  Therefore, considering that the compression rate of the rim mounting portion 38 and the constricted portion 46 is not greatly reduced, the surface distortion in the vicinity of the engagement groove 37 of the tire 33 is not increased, and the opening of the engagement groove 37 is not increased. When the conventional narrow tire 33 shown in FIG. 2 is widened, the left and right width D of the tire outer peripheral portion 39 is larger than the left and right width B of the rim mounting portion 38 as shown in FIG. In this case, as shown in FIG. 4B, when a load is applied to the shoulder portion 48 of the tire outer peripheral portion 39 from the outer side in the wheel radial direction, The amount of deformation of the portion to be shown (outside in the left-right direction and radially inward of the sidewall portion 47) toward the inner side in the radial direction of the wheel increases. As a result, when a load repeatedly acts on the shoulder portion 48, the sidewall portion 7 near the outer end in the left-right direction of the folded portion 36 (at the boundary between the portion of the sidewall portion 47 that is backed up by the folded portion 36 and the portion that is not backed up by the folded portion 36 (j portion)), There arises a problem that cracks due to bending fatigue occur.

  In view of this problem, the present invention provides a laterally outer side of a rim folded portion of a sidewall portion when a load is applied to the shoulder portion of the tire when the lateral width of the tire outer peripheral portion is greatly widened. An object of the present invention is to provide a wheel capable of suppressing bending deformation in the vicinity of the end portion as much as possible, and as a result, capable of widening the tire without significantly reducing the compression rate of the rim mounting portion or the like.

The technical means of the present invention for solving this technical problem includes a wheel and a tire attached to a rim provided on the outer peripheral side of the wheel, and the rim is constituted by a pair of left and right rim components. The left and right rim components are provided with folded portions extending inward in the left-right direction on the outer peripheral side of the rim structure, and provided with engaging grooves on the left and right side surfaces of the tire, and inserting the folded portions into the engaging grooves. In the wheel configured to hold the inner peripheral side of the tire in a hug shape with the left and right rim components,
Both left and right side surfaces of the outer peripheral portion of the tire are formed into inclined surfaces that incline in a direction that shifts inward in the left-right direction as going inward in the tire radial direction with respect to a surface orthogonal to the left-right direction. When the inclination angle of the side surface of the tire outer peripheral portion with respect to the surface orthogonal to
It is characterized by 10 ° ≦ θ ≦ 50 °.

Further, the tire is composed of a tire main body portion having a hollow portion therein and a foam filled in the hollow portion, and an inner peripheral side of the tire main body portion is divided by a split surface extending from the tire inner peripheral surface to the hollow portion. It is good to make it isolate | separate and to fill a cavity with a foam from between this split surfaces.
Further, the tire main body is mainly composed of an inner rim mounting portion mounted on the rim and a tire outer peripheral portion protruding outward in the tire radial direction from the rim, and the tire outer peripheral portion is located on the outer peripheral side of the cavity portion. It has a tread part and side wall parts on the left and right sides of the cavity part,
The radial dimension from the inner peripheral edge of the tire to the position of the engagement groove is a, the radial dimension from the inner peripheral edge to the outer peripheral edge of the tire is b, and the rubber gauge of the tread portion of the tire body is e. When the rubber gauge of the sidewall portion of the outer peripheral portion of the main body portion is f, the left and right width of the rim mounting portion is c, and the left and right width of the tire outer peripheral portion is d,
It is preferable that 0.2 b ≦ a ≦ 0.5 b , 8 mm ≦ e ≦ 12 mm, 5 mm ≦ f ≦ 12 mm, and d / 2 ≦ c <d.

  According to the present invention, when the left and right width of the tire outer peripheral portion is greatly widened, the side wall portion of the side wall portion when a load is applied to the shoulder portion of the tire, in the vicinity of the left and right outer end portions of the folded rim portion. Bending deformation can be suppressed as much as possible, and as a result, the tire can be widened without significantly reducing the compression ratio of the rim mounting portion or the like.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In FIG. 1, reference numeral 1 denotes a wheel. The wheel 1 is mainly composed of a wheel 2 attached to an axle of a vehicle such as a silver car and an annular tire 3 attached to the outer peripheral side of the wheel 2. ing.
The wheel 2 mainly includes a wheel main body 4 and a rim 5 provided on the outer peripheral side of the wheel main body 4. The wheel main body 4 and the rim 5 are a pair of right and left (in the direction of the rotation axis of the wheel 1). The wheel body components 4L, 4R and the rim components 5L, 5R, which are configured by the components 4L, 4R, 5L, 5R and are on the same side in the left-right direction, are integrally formed of a plate material.

The tire 3 is composed of an elastic material such as non-foaming rubber and the like, and a tire main body portion 8 that forms an outline of the tire 3, and a core portion 9 that is formed of a foam provided inside the tire main body portion 8. It is composed of
The tire body portion 8 is formed in a ring shape, and is mainly composed of an inner rim mounting portion 10 mounted on the rim 5 and a tire outer peripheral portion 11 protruding outward in the wheel radial direction from the rim 5. Yes.
Engaging grooves 12 that are located between the tire outer peripheral portion 11 and the rim mounting portion 10 and that extend inward in the left-right direction are formed on the left and right side surfaces of the tire body 8. It is formed over.

In addition, a hollow portion 15 filled with the core portion 9 is formed in the tire main body portion 8 over the entire circumference of the tire 3, and the rim mounting portion 10 is formed in the tire 3 at the center in the left-right direction. The left and right components 10L and 10R are separated by a split surface 14 extending from the peripheral surface to the cavity 15.
The left and right wheel body constituting bodies 4L and 4R are formed in a disc shape and overlapped as a concentric shape, and are fastened at appropriate positions on the outer peripheral side by fasteners 16 made of bolts and nuts. It can be attached as a concentric shape.

The left and right rim constituting bodies 5L and 5R project so as to extend from the outer peripheral side of the left and right wheel main body constituting bodies 4L and 4R to the outer side in the left and right direction and come into contact with the inner peripheral surface of the rim mounting portion 10. A rim bottom portion 17, a rim side portion 18 that extends outward from the extending end of the rim bottom portion 17 in the wheel radial direction and contacts the side surface of the rim mounting portion 10, and an extending end of the rim side portion 18 And a folded portion 19 that extends inward in the left-right direction and is inserted into the engaging groove 12.
In the wheel 1 of the present embodiment, in order to attach the tire 3 to the rim 5, the rim constituting bodies 5L and 5R are arranged on both the left and right sides of the rim attaching portion 10 of the tire 3, and the left and right rim constituting bodies 5L are arranged. The left and right rim components 5L and 5R and the wheel body components 4L and 4R are moved in the approaching direction so that the folded portion 19 of 5R is inserted into the engagement groove 12, and the left and right components 10L of the rim mounting portion 10 are moved. , 10R to hold the rim mounting portion 10 in a holding shape with the left and right rim components 5L and 5R so that the split surface 14 is in close contact, and the left and right wheel body components 4L and 4R are overlapped and fastened. Thus, the rim mounting portion 10 is mounted on the rim 5 (the tire 3 is mounted on the wheel 2).

At this time, the constricted portion 24 formed by the rim mounting portion 10 and the left and right engaging grooves 12 of the tire 3 is compressed by the left and right rim components 5L and 5R, and the rim mounting portion 10 is compressed by the left and right rim components in the compressed state. The rim mounting portion 10 is firmly fixed to the rim 5 by being sandwiched between 5L and 5R.
In the wheel 2, one rim constituting body 5 </ b> L, 5 </ b> R is integrally formed on a single disc-shaped wheel body 4, and the other rim constituting body 5 </ b> L, 5 </ b> R is bolted to the outer peripheral portion of the side surface of the wheel body 4. For example, it may be configured to be fixed by attachment. Further, the wheel body 4 and the rim 5 may be configured separately.

The tire outer peripheral portion 11 is located on the wheel outer peripheral side of the hollow portion 15 and is a portion that contacts the road surface or the like, and the tire outer peripheral portion 11 is located on both the left and right sides of the hollow portion 15 and covers the tread portion 20. And a side wall portion 21 that elastically supports a load, and protrudes outward in the left-right direction from the rim mounting portion 10.
The left and right side surfaces (outer surfaces of the left and right sidewall portions 21) 20 of the tire outer peripheral portion 11 are inward in the left and right direction (the central portion in the left and right direction) as they go inward in the wheel radial direction with respect to the surface orthogonal to the left and right direction. ), And the lower end portions of the left and right side surfaces 22 of the tire outer peripheral portion 11 are in the vicinity of the outer end portion in the left-right direction of the turn-up portion 19 of the rim 5. Is located.

The inclination angle θ of the side surface 22 of the tire outer peripheral portion 11 with respect to the surface orthogonal to the left-right direction is set to 10 ° ≦ θ ≦ 50 °.
When θ> 50 °, the rigidity of the shoulder portion 23 that is a corner portion of the tread portion 20 and the sidewall portion 21 is significantly reduced, and running stability is lacking.
Further, in the case of θ <10 °, when a load is applied to the shoulder portion 23 of the tire main body portion 8, the deformation amount of the portion indicated by the symbol j ′ in FIG. When a load is applied, a crack due to bending fatigue occurs on the side wall portion 21 on the outer end side in the left-right direction of the folded portion 19 of the rim 5.

In addition, since the tire body 8 does not have a reinforcing member such as a cord or a wire and is formed only of a rubber material, the tread 20 is considered in consideration of durability and cushioning properties of the tread 20. The rubber gauge e (at the center in the left-right direction) is preferably 8 mm ≦ e ≦ 12 mm, and preferably 10 mm.
The rubber gauge f of the sidewall portion 21 is preferably 5 mm ≦ f ≦ 12 mm.
Since the side wall portion 21 is a portion that continuously bends in the vertical direction during running, a rubber gauge f of 5 mm or more should be secured in the case of a single rubber. In order to improve the cushioning property, it is effective to set the rubber gauge f of the sidewall portion 21 to be less than 5 mm. However, the durability decreases due to bending fatigue, cut scratches, etc., and the running resistance increases.

Moreover, when the rubber gauge f of the side wall part 21 exceeds 12 mm, cushioning properties are impaired.
FIG. 5 shows the relationship between the rubber gauge (side rubber gauge) f of the sidewall 21 and the cushioning property (longitudinal spring of the tire 3) or running resistance (rotational resistance of the tire 3). For the test, a tire 3 was used which was a foamed rubber having a tire outer diameter: φ280 mm, a right and left width of the tire: 60 mm, a core portion 9 having Asker C hardness: 25 °, and material: EPT.
Further, the radial dimension a from the inner peripheral end of the tire 3 to the position of the engagement groove 12 and the radial dimension (thickness in the radial direction of the wheel 1) b from the inner peripheral end to the outer peripheral end of the tire 3 Relationship
0.2 b ≦ a ≦ 0.5b.

When a <0.2b, the rim 5 of the wheel 2 does not have enough force to hold (hold) the tire 3, the tire outer peripheral portion 11 wobbles and the running stability is impaired, and the rim mounting portion 10 is detached from the rim 5. The possibility increases.
On the other hand, in the case of a> 0.5b, the radial thickness of the tire outer peripheral portion 11 becomes thin, and sufficient cushioning properties cannot be obtained.
The relationship between the left and right width c of the rim mounting portion 10 and the left and right width d of the tire outer peripheral portion 11 in a state where the tire 3 is set on the wheel 2 is as follows.
d / 2 ≦ c <d.

In the case of c <d / 2, the rigidity of the shoulder portion 23 is lowered, and traveling stability is impaired.
Further, in the case of c ≧ d, the rim 5 protrudes outward in the left-right direction from the tire outer peripheral portion 11, and the wheel 2 is damaged by contact with a wall or the like during traveling, and may be deformed in some cases. Problems such as increased runout of the tire 3 occur.
The core portion 9 is made of a foamed material such as rubber or urethane, and preferably has a hardness of 25 ° to 50 ° (Asker C type).
The core portion 9 is foamed after injecting a non-foamed material into the cavity portion 15 through the split surface 14 of the rim mounting portion 10 into the tire body portion 8 that has been press-molded with a molding die, or added with a molding die. By inserting a core portion 9 formed by casting and foaming into a tire main body portion 8 that has been flow-molded so as to match the shape of the cavity portion 15 into the cavity portion 15 from between the split surfaces 14 of the rim mounting portion 10. The hollow portion 15 of the main body portion 8 is filled.

High-level rotation resistance (running resistance) for low-cost, bottom-vibration wheels that hold the inner periphery of a hollow tire like a conventional one in the shape of a hug between left and right rim components And there is a limit to improve both performances simultaneously due to the structure, and in some cases, the required performance may not be satisfied.
In addition, the tire body portion is formed by heating and pressure-molding an unfoamed material constituting the core portion embedded in an unvulcanized elastic material constituting the tire body portion and integrating them in a molding die. If the core portion is foamed inside the tire main body portion at the same time as the vulcanization molding, there are problems such as high manufacturing costs and variations in the position of the core portion.

  Therefore, as in the present embodiment, after the tire main body portion 8 is vulcanized, the core portion 9 is filled in the tire main body portion 8 in the tire main body portion 8 in the post process by the injection method or the insertion method. Compared to the hollow type tire 3, it is possible to meet demands for cushioning and running resistance at a higher level and to provide an inexpensive tire 3 (wheel).

It is sectional drawing of the wheel concerning this invention. It is sectional drawing of the wheel concerning a prior art example, and sectional drawing of a tire. It is sectional drawing of the wheel concerning a comparative example. It is sectional drawing of the wheel concerning a comparative example. (A) is a graph which shows the relationship between the rubber gauge (side rubber gauge) of a sidewall part, and cushioning properties (longitudinal spring of a tire), (b) is the rubber gauge (side rubber gauge) of a sidewall part, and running resistance ( It is a graph which shows the relationship with the rotation resistance of a tire.

Explanation of symbols

2 Wheel 3 Tire 5 Rim 5L Rim structure 5R Rim structure 8 Tire body 9 Core (foam)
DESCRIPTION OF SYMBOLS 10 Rim mounting part 11 Tire outer peripheral part 12 Engagement groove 14 Split surface 15 Cavity part 19 Folding part 20 Tread part 21 Side wall part 22 Side surface of outer peripheral part of tire a Diameter from inner peripheral end of tire to position of engaging groove Dimensional dimension b Radial dimension from the inner circumference edge to the outer circumference edge of the tire c Left and right width of the rim mounting part d Left and right width of the tire outer circumference e Rubber gauge of the tread part f Rubber gauge of the sidewall part θ Tire with respect to a plane orthogonal to the right and left direction Inclination angle of side of outer periphery

Claims (3)

A wheel (2) and a tire (3) mounted on a rim (5) provided on the outer peripheral side of the wheel (2), the rim (5) being a pair of left and right rim components (5L, 5R) Folded portions (19) that extend inward in the left-right direction are provided on the outer peripheral side of the left and right rim components (5L, 5R), and engagement grooves ( 12), and the folded portion (19) is inserted into the engagement groove (12) so that the inner peripheral side of the tire (3) is clamped between the left and right rim components (5L, 5R). In the wheel configured in
Inclinations that incline the left and right side surfaces (22) of the outer peripheral portion (11) of the tire (3) in a direction that shifts inward in the left-right direction as it goes inward in the wheel radial direction with respect to the surface orthogonal to the left-right direction. When the inclination angle of the side surface (22) of the tire outer peripheral portion (11) with respect to the surface orthogonal to the left-right direction is θ,
A wheel characterized in that 10 ° ≦ θ ≦ 50 °. The tire (3) is composed of a tire main body (8) having a hollow portion (15) therein and a foam (9) filled in the hollow portion (15). The inner peripheral side is separated by a split surface (14) extending from the tire inner peripheral surface to the cavity (15), and the foam (9) is filled into the cavity (15) from between the split surfaces (14). The wheel according to claim 1, wherein The tire body portion (8) is mainly composed of an inner rim mounting portion (10) mounted on the rim (5) and a tire outer peripheral portion (11) protruding outward in the wheel radial direction from the rim (5). The tire outer peripheral part (11) has a tread part (20) on the outer peripheral side of the cavity part (15), and sidewall parts (21) on both the left and right sides of the cavity part (15),
The radial dimension from the inner peripheral end of the tire (3) to the position of the engagement groove (12) is a, the radial dimension from the inner peripheral end to the outer peripheral end of the tire (3) is b, and the tread portion (20 ) Is set to e, the rubber gauge of the sidewall portion (21) is set to f, the left and right width of the rim mounting portion (10) is set to c, and the left and right width of the tire outer peripheral portion (11) is set to d.
The wheel according to claim 2, wherein 0.2 b ≦ a ≦ 0.5 b , 8 mm ≦ e ≦ 12 mm, 5 mm ≦ f ≦ 12 mm, and d / 2 ≦ c <d.

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