JPH0121041Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tire wheel centering device for coaxially positioning a tire wheel to a rotating hub when the tire wheel is attached to the rotating hub.

Attach the tire wheel to the rotating hub of the vehicle,
When installing to the rotating hub of a tire testing device such as a tire uniformity measuring device or tire balancer measuring device, insert the hub bolts protruding from the rotating hub into the multiple through holes formed around the axis of the tire wheel. A hub nut is tightened onto the tip of this bolt, and the tire wheel is fixed to the rotating hub using the tapered cone of the hub mat.

The accuracy with which the tire wheel and wheel hub are assembled in this way depends on the manufacturing accuracy of a plurality of through holes formed around the axis of the tire wheel. Due to the machining accuracy of the tire wheel's through-holes and the machining accuracy (approximately 0.2 mm) of the axial center runout of the hub bolt fixed to the rotating hub, center runout (eccentricity) occurs when the tire wheel is installed. In addition, vibration is caused by the generation of excitation force from the tire, and in addition, in the case of a tire tester, it is a cause of measurement error.

In this way, when installing a conventional tire wheel, the axis center of the tire when the tire wheel is installed is affected by the manufacturing accuracy of the hub bolt, the processing accuracy of the tire wheel through hole for inserting the hub bolt, and the fitting accuracy when installing the tire. Center run-out (eccentricity) of rotating Abs is unavoidable.

Conventionally, as a tire wheel centering device when assembling such a tire wheel, a nut with a tapered outer periphery and coaxially screwed onto the rotating hub is used, and the tapered outer periphery of this nut is inserted into the center hole of the tire wheel. It has also been attempted to attach a tire wheel to a rotating hub with high precision by engaging it with the peripheral wall (see Japanese Patent Publication No. 18642/1983 and Japanese Utility Model No. 55501/1983).
If there is a protrusion or burr in the center hole of the tire wheel, this part will come into contact with the outer periphery of the nut, resulting in uneven friction due to uneven contact of the nut taper, or the tire wheel will be attached eccentrically to the rotating hub.

The present invention takes the above facts into consideration and aims to provide a tire wheel centering device that can accurately attach a tire wheel to a rotating hub.

In the present invention, with the tire wheel 10 in contact with the flange portion 20A of the rotating hub 20, the centering nut 28 is screwed onto the rotating hub, and the centering nut 28 is screwed into the center hole 30 of the tire wheel.
The tire wheel centering device positions the tire wheel coaxially with a rotating hub by engaging with the rotating hub, and a tapered portion 20C is formed coaxially with the rotating hub on the outer periphery of the rotating hub. The centering nut has a cone portion 28B, 4 in which a plurality of slits 38 are formed along the axial direction at the tip.
0.50B is formed, and when the centering nut is screwed into the rotating hub, the tip of the centering nut engages with the tapered part, and the cone part receives a radially outward expanding force. It is characterized in that it deforms and engages with the inner periphery of the center hole of the tire wheel, coaxially positioning the tire wheel to the rotating hub by a wedge action.

If the center hole of the tire wheel is significantly misaligned with the centering nut before centering, the outer circumference of the cone of the centering nut may not be the entire circumference due to the threading of the centering nut onto the rotating hub. Only a portion of it will come into contact with a part of the inner periphery of the center hole of the tire wheel. However, in the present invention, since the cone part has a slit, each cone part divided by the slit can be elastically deformed, and even if an unbalanced force is applied to the outer periphery of the cone part, this can be absorbed by the elastic deformation of the cone part. This prevents center runout of the tire wheel.

Even if there is a protrusion or burr in the center hole of the tire wheel, the cone portions separated through the slit will expand radially outward and engage with the inner periphery of the center hole of the tire wheel. A tire wheel can be attached with high precision without causing large wear.

FIG. 1 is a comparative example showing a comparison with the present invention, and shows a structure applied when attaching a tire wheel 10 to a spindle 12 of an actual vehicle.

The spindle 12 is integrally fixed to the knuckle arm 14 and projects horizontally, and a cylindrical rotating hub 20 is pivotally supported on the spindle 12 via bearings 16 and 18. As shown in FIG. 2, this rotary hub 20 is formed with a disk portion 20A as a flange portion projecting radially from an axially intermediate portion, and a plurality of hub bolts 22 are fixed to this disk portion 20A. has been done. A plurality of these hub bolts 22 are arranged upright at equal intervals around the axis of the spindle 12, and are inserted into a through hole 24 formed in the tire wheel 10, and a hub nut 26 is tightened from the opposite side of the tire wheel 10. By doing so, the tire wheel 10 is securely rotated by the hub 2.
It has become fixed at 0. In the conventional structure, a tapered portion 26A is generally formed at one end in the axial direction of the hub nut 26;
The wedge action of A causes the through hole 24 to form the tapered portion 2.
6A to position the tire wheel 10.

The rotary hub 20 has one axial end protruding in a cylindrical shape near the outer periphery of the tip end of the spindle 12, and has a male thread 20B carved on the outer periphery so that a centering nut 28 is screwed into the rotating hub 20.

This centering nut 28 has a cylindrical shape, and has a female thread 28A carved on the inner periphery for screwing with a male thread 20B, and a tapered cone portion 28B whose diameter gradually decreases toward the tip on the outer periphery tip.
is provided.

Also, this centering nut 28 is connected to the taper cone portion 2.
A cover plate 30 is integrally formed at the axial end opposite to 8B, and by fixing a nut 32 to this cover plate 30, the nut 32 absorbs the rotational force of a tool such as a spanner (not shown). The centering nut 28 is rotated by receiving the centering nut 28.

The tapered cone portion 28B is adapted to engage with a center hole 36 that is the inner circumferential surface of a burring 34 formed in the axial core portion of the tire wheel 10. This center hole 36 is a reference hole when processing the tire wheel 10, and other processes are positioned using this center hole 36 as a reference.

With this structure constructed in this way, the tire wheel 1
0 to the rotating hub 20 will be explained.

The tire wheel 10 is arranged coaxially with the rotating hub 20 and is pressed against the rotating hub disk portion 20A. As a result, the hub bolt 22 is inserted into the through hole 24 of the tire wheel 10, and the tip portion protrudes from the opposite side.

In this state, the centering nut 28 is screwed onto the rotating hub 20. The tapered cone portion 28B is pushed toward the inner periphery of the center hole 36 of the tire wheel 10 by the axial movement due to this screw engagement. As a result, the taper cone portion 2
8B positions the axis of the tire wheel 10 accurately and coaxially with the axis of the rotating hub 20 by a wedge action.

After positioning the tire wheel 10, the hub nut 26 is screwed onto the hub bolt 22 and the tire wheel 10 is strongly pressed against the disk portion 20A of the rotating hub, thereby completing the assembly of the tire wheel 10.

Since the center hole 36 of the tire wheel 10 is accurately held coaxially with the rotating hub 20, variations in the load on the tire shaft caused by the tire due to misalignment are reduced, disturbance to the vehicle is reduced, and vibrations are reduced. etc. will be less likely to occur. Additionally, a tire testing machine has the advantage of reducing measurement errors due to misalignment and increasing measurement accuracy.

Next, a first embodiment of the present invention will be described. In this embodiment, the taper cone portion 28B is expanded in the radial direction of the rotating hub 20 when the centering nut 28 is screwed on. That is, as shown in FIG. 3, a plurality of slits 38 are cut along the axial direction in a taper cone portion 28B formed at the tip of the centering nut 28, so that the taper cone portion 28B can expand and contract in the radial direction. On the other hand, a tapered portion 20C is coaxially formed in the rotating hub 20 between the male screw 20B and the disk portion 20A, and is adapted to engage with the tapered cone portion 28B.

The effect of the plurality of slits 38 in the first embodiment shown in FIG. 3 being cut along the axial direction will be explained with reference to FIGS. 4 and 5.

Considering the case where the slits 38 expand coaxially due to uniform pressure, the distribution of the acting force F _A on the thin arc-shaped member 28B of each slit will be symmetrical as shown in FIG. It is.

On the other hand, if we consider the case where the slit 38 expands due to being unevenly pressed or partly getting caught in minute protrusions such as burrs, as shown in FIG.
Acting force of the thin arc member 28B of a specific slit
It is conceivable that the distribution of F _A becomes asymmetrical, and that the acting force F _A does not act on the center of the taper cone portion, causing a lateral force Y. The lateral force Y causes the arc-shaped member 28B to bend in the cylindrical plane since the arc-shaped member 28B is carved with the slits 38A and 38B, but the deformation remains within the width of the slit, and the arc-shaped member 28B is bent.
8B will expand coaxially and uniformly due to X, which is the radial component of the acting force.

As a result, when the centering nut 28 is screwed onto the rotary hub male thread 20B, the taper cone portion 28B expands, and an even pushing force is applied to the center hole 36 of the tire wheel 10, allowing firm positioning.

Next, FIG. 6 shows a centering structure according to a second embodiment of the present invention.
Similar to the embodiment, a tapered portion 2 is provided on the outer periphery of the rotating hub 20.
0C is formed.

However, unlike the above embodiments, the centering nut 28 does not have a tapered cone at the tip of its outer periphery, and has a straight outer periphery having the same radius. However, a tapered cone portion 40 is formed at the inner peripheral portion of the tip of the centering nut 28, and is adapted to engage with the tapered portion 20C. Furthermore, this centering nut 2
8 is also formed with a plurality of slits similar to those in the previous embodiment, so that the taper cone portion 40 can be expanded.

Therefore, in this embodiment, by rotating the nut 32, the centering nut 28 is attached to the rotating hub male thread 20B.
When tightened, the taper cone portion 40 engages with the taper portion 20C and expands in the radial direction, and the outer peripheral tip of the centering nut engages with the center hole 36 of the tire wheel 10 to accurately hold the tire wheel 10. Can be centered.

Next, FIG. 7 shows a centering structure according to a third embodiment of the present invention. In this embodiment, the third
As in the embodiment, the rotating hub 20 has a male thread 20B and a tapered portion 20C, and the centering nut 28 has a female thread 28A and a tapered cone portion 40 on its inner circumference. Further, as shown in FIGS. 8 and 9, the centering nut 28 has a plurality of slits 38 in the axial direction.
is formed so that an even pushing force is generated during expansion.

However, in this embodiment, a step 42 is formed between the female thread 28A on the inner periphery of the centering nut 28 and the taper cone portion 40, and thin step portions 44 and 46 are formed in the axially intermediate portion of the outer periphery. The reduced rigidity (elasticity) of the thin stepped portion makes it easier to expand, eliminates unnecessary force during attachment, and makes attachment and detachment ideal and easy.

Next, FIG. 10 shows a fourth embodiment of the present invention, in which the centering nut is attached to the threaded ring 4.
8, an engaging ring 50, and a centering sleeve 58, and the spindle 12 is fixed to a tire tester.

The threaded ring 48 has a male thread 48A formed on the outer periphery of its tip and is adapted to be threaded into a female thread of the rotating hub 20. A flange 54 protruding inward from an engagement ring 50 inserted from the outer periphery of the male thread 48A is in contact with a flange 52 protruding from the axial end of the threaded ring 48 on the side opposite to the male thread 48A. Furthermore, a stopper ring 56 is inserted into the outer periphery of the threaded ring 48 to prevent the engagement ring 50 from being pulled out. The threaded ring 48 is provided with a rotating nut 3 as in each of the above embodiments.
2 is fixed.

As shown in FIGS. 11 and 12, the engagement ring 50 has a plurality of slits 38 formed from the opposite axial end of the collar portion 54, and this end is connected to the expanded portion 50A.
It is said that The outer periphery of this expanded portion 50A is cylindrical, but the tip of the inner periphery is a tapered cone portion 50B. Therefore, this engagement ring 50 is formed by screwing the threaded ring 48 onto the rotating hub 20, thereby forming the expanded portion 50A.
engages with the tapered portion 20C and expands evenly in the radial direction.

This expanded portion 50A can be directly engaged with the center hole 36 of the tire wheel 10, but in this embodiment, it is connected to the center hole 36 of the tire wheel through a centering sleeve 58 shown in FIGS. 13 and 14. It's starting to come into contact with people.

The centering sleeve 58 has a cylindrical shape, and a plurality of slits 60 and 62 are alternately formed from both ends in the axial direction, so that it can easily expand and deform in the radial direction. The centering sleeve 58 has an inner circumferential portion corresponding to the expanded portion 50A of the engagement ring 50, and an outer circumferential portion corresponding to the tire wheel center hole 36.

Therefore, in the centering operation in this embodiment, the tire wheel 10 is brought into contact with the disk portion 20A of the rotating hub 20, and the hub bolt 22 is inserted into the tire wheel through hole 24.
After inserting the centering sleeve 58 into the center hole 36. Here, if the threaded ring 48 to which the engagement ring 50 is attached in advance is threaded onto the rotating hub 20, the expanded portion 50A of the engagement ring 50 will become the tapered portion 20C.
Since the centering sleeve 58 is engaged with and expanded, the centering sleeve 58
expands in the radial direction and applies an even pushing force to the center hole of the tire wheel. This positions the tire wheel 10, and after this positioning, the hub nut 26 is screwed on to complete the accurate assembly of the tire wheel 10.

In each of the above embodiments, the centering nut 28 can be removed after the hub nut 26 is tightened.

Next, FIGS. 15 to 17 are diagrams showing comparison results between a conventional centering structure using a hub nut and a centering structure using a center hole according to the fourth embodiment of the present invention, and are diagrams showing the results of a comparison between a centering structure using a conventional hub nut and a centering structure using a center hole according to a fourth embodiment of the present invention. Radial Hose Variation (RFV) is the amount of variation in the radial load applied to the tire shaft.
The values are shown below. According to this, it has been found that the variation in measured values of the present invention is reduced without affecting the type of tire, and highly accurate assembly is possible. That is, when tire A is installed using the conventional method, the RFV value shows a variation of 7.5 kg to 10.8 kg, but according to the fourth embodiment, the RFV value is within the range of 9.5 kg to 10.5 kg. It became. Furthermore, tire B, tire C
In the case of , it can be seen that the range of variation of 3 to 4 kilograms has become half that, 1 to 1.5 kilograms.

As explained above, in the present invention, with the tire wheel 10 in contact with the flange portion 20A of the rotating hub 20, the centering nut 28 is screwed onto the rotating hub and engaged with the center hole 36 of the tire wheel. The tire wheel centering device is a tire wheel centering device that positions coaxially with a rotating hub, in which a tapered portion 20C is formed coaxially with the rotating hub on the outer periphery of the rotating hub, and the centering nut has an axis extending toward the tip. A plurality of slits 38 are formed along the direction, and cone portions 28B, 40, and 50B are formed whose wall thickness decreases toward the tip, and the centering nut is screwed into the rotation hub of the centering nut. The tip of the pop-out nut engages with the tapered part, and the cone part deforms under the force of expanding outward in the radial direction, engages with the inner periphery of the center hole of the tire wheel, and wedges the tire wheel. Since it is positioned coaxially with the rotating hub, it has the excellent effect of allowing the tire wheel to be assembled with high precision without causing large wear on the tapered portion.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a tire wheel centering device according to a comparative example of the present invention, FIG. 2 is a partially enlarged view of FIG. 1, and FIG. 3 is a side view showing a first embodiment of the present invention. (The carrying centering nut is shown in perspective), the fourth
5 and 5 are explanatory diagrams of the effect of the slit, and FIG. 6 is a sectional view showing the second embodiment of the present invention.
FIG. 7 is a sectional view showing the third embodiment of the present invention;
The figure is a sectional view showing a centering nut used in the third embodiment of the present invention, FIG. 9 is a left side view of FIG. 8, and FIG. 10 is a left side view of FIG.
11 is a sectional view of a centering nut used in the fourth embodiment, FIG. 12 is a left side view of FIG. 11, and FIG. 13 is a sectional view of the fourth embodiment of the present invention. FIG. 14 is a front view of the centering sleeve used in the example, FIG. 14 is a right side view of FIG. 13, and FIGS. 15 to 17 are diagrams showing comparison results between the fourth embodiment and the conventional technology. 10...tire wheel, 12...spindle,
20... Cylindrical rotating hub, 22... Hub bolt,
24...Through hole, 26...Hub nut, 28...
Centering nut, 36... Center hole, 40... Taper cone portion, 48... Threaded ring, 50... Engagement ring, 5
8...Centering sleeve.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) With the tire wheel 10 in contact with the flange portion 20A of the rotating hub 20, the centering nut 28 is screwed onto the rotating hub and engaged with the center hole 36 of the tire wheel. A tire wheel centering device for positioning a tire wheel coaxially with a rotating hub, wherein a tapered portion 20C is formed coaxially with the rotating hub on the outer periphery of the rotating hub, and the centering nut includes a tapered portion 20C coaxially with the rotating hub. A cone portion 28B, 4 in which a plurality of slits 38 are formed along the axial direction at the tip.
0.50B, and when the centering nut is screwed into the rotating hub, the cone portion engages with the tapered portion and is deformed by receiving a radially outward expanding force, thereby causing the tire wheel to A tire wheel centering device that engages with the inner periphery of a center hole of the tire wheel and coaxially positions the tire wheel with respect to a rotating hub by a wedge action. (2) The centering nut has a threaded ring 4 having a threaded portion.
8, an engagement ring 50 in which the cone portion and the slit are formed, the engaging ring 50 is arranged coaxially with the rotating hub, and is moved in the axial direction of the rotating hub by screwing the threaded ring into the rotating hub; A tire wheel centering device according to claim (1) of the above-mentioned utility model registration. (3) A sleeve 58 that can be expanded in the radial direction is provided between the outer periphery of the cone portion and the center hole of the tire wheel.
The tire wheel centering device according to claim 1 or 2 of the utility model registration claim, characterized in that: