JPH11258097A - Weight unbalance correcting method for tire-rim assembly and tire-rim assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the weight applied in balancing a tire-rim assembly. SOLUTION: An average static balancing amount Bs in a bead base part 14A of a mother group of a tire 10 installed in a rim 12 is determined, and in the drop center position 16 of the rim, a static unbalance correcting weight 18 of weight WS determined from the expression: weight WS=Bs×(radius r1 from the axis of rotation to the center of gravity of the static unbalance correcting weight)/(radius of the bead base part), is applied. The direction of the weight 18 and the direction of the point of the tire 10 are aligned to perform rim assembling. As the static balance is obtained by assembling the tire 10 in the rim 14, the balance weight by subsequently balancing the tire-rim assembly finally can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting a weight imbalance of a tire / rim assembly and a tire / rim assembly having a corrected weight imbalance.

[0002]

2. Description of the Related Art It is well known that vibration occurs when a tire / rim assembly is rotated in an avant-garde condition.

[0003] The imbalance includes a static imbalance in which 360 ° existing without rotation is heavy, and a dynamic imbalance generated when rotation is started.

One method of correcting such imbalance is to first correct the static imbalance, then rotate the tire / rim assembly and use a separate balance weight to correct the dynamic imbalance. is there.

However, at present, mainly, the tire / rim assembly is rotated by a balancer to measure the resultant force of the static balance and the dynamic balance required for correction, and based on this, one at each of the front and back surfaces of the rim flange. Attempts have been made to simultaneously correct static balance and dynamic balance by attaching a balance weight.

[0006]

However, in this weight imbalance correction method, even if the wheel unbalance amount is zero, it is necessary to correct the tire imbalance amount.

When the static and dynamic balances are divided as compared with the two-point balance where two balance weights are added at the front and back, as shown in FIG. weight 2W when put one balance weight of _S), weight dynamic balance to 2WD (1 point W
If put one balance weight of d), and static balance installation point, the weight of the front and back two positions balanced and the angle smaller that form in the direction of rotation of the dynamic balance installation point and θ is, W1 = (W _S ^{2 _{+ Wd 2 +2 · W S ·}} Wd · cosθ)
^{_{1/2 W2 = (W S 2 +}} Wd 2 -2 · W S · Wd · cosθ)
^1/2 .

In comparison, the total weight of the balance weights separated into the static balance and the dynamic balance is heavier than the total weight of the two balance weights shown in FIG.

Therefore, in the present situation where lead is used as the balance weight, considering the effect on the environment, the balance correction is not always satisfactory in terms of the amount of lead used.

At the present time, it is difficult to substitute the balance weight of lead from the viewpoint of specific gravity.

That is, when the conventional balance method is adopted, lead cannot be reduced in terms of environment.

The present invention has been made in consideration of the above-described circumstances, and has as its object to provide a method for correcting a weight unbalance of a tire / rim assembly and a tire / rim assembly with a corrected weight imbalance that can reduce the balance weight as much as possible. It is.

[0013]

The inventor of the present invention has conducted various investigations on tires to be mounted on a rim. As a result, the static imbalance of the tire itself is substantially constant if the tires have the same size and the same name (brand) of the same manufacturer. If the weight that corrects the static imbalance of the tire is attached in advance to the rim where this tire is assembled, the amount of weight given when the tire / rim assembly is balanced can be reduced. I found that.

The invention according to claim 1 has been made in view of the above fact, and the weight imbalance of the tire / rim assembly when the balance weight added to the rim is separated into a static balance and a dynamic balance. In a correction method, an average static balance amount Bs at a bead base portion of a population of tires to be mounted on a predetermined rim is obtained, and a center of a drop center at 360 ° around the rim is calculated by the following equation (1). A rim provided with the weight amount WS determined from the above is prepared, and when viewed from the rotation axis, the weight amount WS is set so that the direction of the weight amount WS and the direction of the light point of the tire are the same. Assembling the tire on the rim provided with the rim, and then applying a dynamic balance to the rim by taking a dynamic balance and reducing the dynamic imbalance. It is characterized in.

WS = Bs × radius r 1 from the rotation axis to the center of gravity of the weight for correcting static imbalance / radius of the bead base portion..Formula (1) The tire / rim assembly according to claim 1. In the weight imbalance correction method, first, prepare a plurality of tires to be mounted on the rim, obtain the amount of static balance of each tire with a balancer, and calculate the average static balance at the bead base required to correct the static imbalance. Calculate the quantity Bs.

Next, a weight amount WS at the center of the drop center of the rim corresponding to the average static balance amount Bs is determined by the following equation (1), and a weight for correcting the static imbalance of the weight amount WS is assigned to the drop center. Prepare the rim located at the center position.

WS = Bs × radius r 1 from the rotating shaft to the center of gravity of the static imbalance correcting weight / radius of the bead base portion ... Formula (1) Next, the weight amount WS as viewed from the rotating shaft Assemble the tire on the rim so that the direction of the static imbalance correction weight and the direction of the light point of the tire are in the same direction, and then take a dynamic balance to reduce the dynamic imbalance. The balance weight for target imbalance is given to the rim.

According to the present invention, the tire and the rim can be statically balanced by assembling the tire to the rim, so that the tire / rim assembly only needs to correct the dynamic imbalance, and the dynamic The balance weight for imbalance can be reduced.

Further, since the static balance is obtained with one static imbalance correction weight, the weight for correcting the static imbalance can be minimized. Further, since there is only one static imbalance correcting weight and the static imbalance correcting weight is provided at the center position of the drop center of the rim, a dynamic imbalance is generated by adding the static imbalance correcting weight. Nothing.

A tire / rim assembly according to a second aspect is characterized in that the weight imbalance is corrected by the weight / unbalance correction method for a tire / rim assembly according to the first aspect.

In the tire / rim assembly according to the second aspect, the weight imbalance is corrected by the weight / unbalance correction method for the tire / rim assembly according to the first aspect. The balance weight for correcting the imbalance of the above becomes smaller than before.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS.

1 to 3, 10 is a pneumatic tire, 12 is a rim, C is a rotation center, 14 is a bead portion of the pneumatic tire 10, 14A is a bead base portion of the bead portion 14, and 16 is a rim 12 Wheel drop center, 1
Reference numeral 9 denotes a flange of the rim 12, and CL denotes an equatorial plane (center plane in the width direction) of the rim 12 and the pneumatic tire 10.

In the present embodiment, first, a plurality of pneumatic tires 10 to be assembled to a predetermined rim 12 are prepared, and the static unbalance amount and the position of the light point of each pneumatic tire 10 are measured by a balancer. An average static balance amount Bs in the bead base portion 14A required for correcting the static imbalance is calculated from the measurement result of the pneumatic tire 10, and a light spot mark 17 is provided on the side surface of each pneumatic tire 10.

Next, a weight WS at the drop center center position 16 of the rim 12 corresponding to the average static balance amount Bs is obtained by the following equation (1).
A weight 18 for correcting static imbalance of the S is attached to the drop center center position 16 of the rim 12.

WS = Bs × Radius r 1 from the rotation axis C to the center of gravity of the weight 18 for correcting static imbalance / radius r 2 of the bead base portion 14 A (1) Next, as viewed from the rotation axis C, The direction of the weight 18 for correcting static imbalance and the light mark 1 of the pneumatic tire 10
The pneumatic tire 10 is mounted on the rim 12 so that the direction of the tire 7 is the same as the direction of the tire 7.

Thereafter, the dynamic imbalance of the rim 12 to which the pneumatic tire 10 is attached, that is, the tire / rim assembly is measured by a balancer, and the dynamic imbalance made of lead is used to reduce the dynamic imbalance. Balance weight 2
0 is attached to the flange 19 of the rim 12.

In the present invention, the tire and the rim 12 can be statically balanced by assembling the tire to the rim 12. Thereafter, the tire / rim assembly only needs to correct the dynamic imbalance, and the final applied dynamic The balance weight 20 for the target imbalance can be reduced, and the amount of lead used can be reduced.

The material of the balance weight 20 for dynamic imbalance may be a metal other than lead.

[0030]

As described above, the tire of the present invention
According to the method of correcting the weight imbalance of the rim assembly,
It has an excellent effect that the amount of weight given when balancing the tire / rim assembly can be reduced.

Further, according to the tire / rim assembly of the present invention, there is an excellent effect that the amount of weight given when balancing the tire / rim assembly is smaller than in the past.

[Brief description of the drawings]

FIG. 1 is a side view of a tire / rim assembly.

FIG. 2 is a perspective view of a rim.

FIG. 3 is a sectional view taken along line 3-3 of the tire / rim assembly shown in FIG. 1;

FIG. 4A is a model in which a static balance and a dynamic balance are divided, and FIG. 4B is a model of a two-point balance in which a balance weight is added to two places on the front and back.

[Explanation of symbols]

 Reference Signs List 10 Pneumatic tire 12 Rim 14A Bead base 16 Drop center center position 18 Weight for static imbalance correction

Claims (2)

[Claims] 1. A method for correcting a weight imbalance of a tire / rim assembly when a balance weight added to a rim is separated into a static balance and a dynamic balance, wherein a bead of a population of tires mounted on a predetermined rim is provided. An average static balance amount Bs at the base portion is obtained, and a weight for correcting static imbalance of the weight amount WS obtained from the following equation (1) is applied to one center of the drop center at 360 ° around the rim. The tire is mounted on a rim provided with the weight amount WS so that the direction of the weight amount WS is the same as the direction of the light point of the tire when viewed from the rotation axis. A tire for obtaining a dynamic balance by adding a balance weight for correcting a dynamic imbalance to reduce the dynamic imbalance to the rim. Weight unbalance correction method of the rim assembly. WS = Bs × radius r1 from the rotating shaft to the center of gravity of the static imbalance correcting weight / radius of the bead base portion: Equation (1) 2. A tire / rim assembly whose weight imbalance has been corrected by the method for correcting weight imbalance of a tire / rim assembly according to claim 1.