JP3891702B2 - Tire uniformity measurement correction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for measuring and correcting tire uniformity.
[0002]
[Prior art]
The tire uniformity is measured by pressing the rotating drum against the rotating tire and measuring the force acting on the rotating drum. The magnitude of variation in force in the tire radial direction, which is the main tire uniformity component, is RFV ( Radial Force Variation), the magnitude of force variation in the lateral direction (axial direction) of the tire LFV (Lateral Force Variation), etc. are measured.
[0003]
Based on the measurement result, the outer peripheral surface of the tire is ground by the grinder mechanism so that the RFV and the like are substantially constant over the entire circumference, and the uniformity is corrected.
In particular, RFV uniformity correction is performed simultaneously while measuring the uniformity by pressing a rotating drum against the tire.
[0004]
[Problems to be solved by the invention]
Therefore, during the uniformity correction, the rotating drum is pressed against the tire being corrected for measurement, and during that time it cannot be used to measure another tire.
[0005]
In other words, a uniformity measuring and correcting apparatus having a configuration in which a rotating drum is disposed between both lines in the middle of a two-line tire conveyance path, and the same rotating drum is commonly used for measuring uniformity of tires conveyed on both lines. Then, while the tire is being corrected on one line, the rotating drum is pressed against the tire to perform measurement, and cannot be used for uniformity measurement on the other line.
[0006]
Therefore, until the tire uniformity correction is completed in one line, the other line is in a standby state and the conveyance of the tire is stagnated, so that the work efficiency is lowered.
[0007]
The present invention has been made in view of the above points, and the object of the present invention is to provide a tire uniformity that can improve work efficiency without having to always measure the uniformity of the tire while correcting the uniformity of the tire. The point is to provide a measurement correction method.
[0008]
[Means for solving the problems and effects]
In order to achieve the above object, the present invention measures a force generated when a tire rotates by pressing a rotating drum against a rotating tire supported by a rim shaft, and grinding is performed by a grinder mechanism based on the measurement result. In the tire uniformity measurement correction method for performing uniformity correction, a measurement correction process for correcting simultaneously while measuring, a correction characteristic detection process for detecting a correction characteristic of a tire from a correction state in the measurement correction process, and the correction characteristic detection The tire uniformity measurement and correction method includes at least a prediction process for predicting the correction end time from the correction characteristics of the tire detected in the process and a prediction correction process for performing only the correction until the correction end time predicted in the prediction process.
[0009]
It is a prediction correction process in which the correction characteristic of the tire is detected from the measurement result while correcting in the measurement correction process, the correction end time is predicted based on the correction characteristic, and only the correction is performed until the predicted correction end time. Therefore, it is not necessary to always measure the uniformity of the tire while correcting the uniformity of the tire.
[0010]
Therefore, when in the tire prediction correction process, the rotating drum is released from the uniformity measurement of the tire, so it can be used for the uniformity measurement of other tires, and the overall work efficiency can be improved.
[0011]
According to a second aspect of the present invention, in the tire uniformity measurement correction method according to the first aspect, in the correction characteristic detecting step, a characteristic of a change in a measured value due to grinding for each tire rotation is detected as a tire correction characteristic, and the prediction is performed. In the process, the time when the measured value will reach the target value is predicted from the correction characteristics of the tire as the correction end time.
[0012]
When correction is performed by grinding the tire with the grinder mechanism, the uniformity measurement value changes with each rotation of the tire, and the characteristics of the tire correction can be detected from the state of the change. By continuing, it is possible to predict the time until the measured value reaches the target value, that is, the correction end time, so only the uniformity correction by grinding is performed until the predicted correction end time, and the rotating drum is measured from the measurement of the tire. Can be released and used for other tire measurements.
[0013]
According to a third aspect of the present invention, in the tire uniformity measurement and correction method according to the first or second aspect, in the correction characteristic detecting step, the tire in relation to the magnitude of the force variation in the tire radial direction among the tire uniformity components. A correction characteristic is detected, and in the predictive correction step, the magnitude of force fluctuation in the tire radial direction is corrected.
[0014]
Of the tire uniformity component, the magnitude of force variation in the tire radial direction RFV (Radial Force Variation) detects the correction characteristic from the correction state, predicts the correction end time from the correction characteristic, and predicts the RFV until the correction end time Make corrections.
During the RFV predictive correction, the rotating drum can be released from the tire measurement and used for other tire measurements.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 is a partially omitted plan view of a tire uniformity measurement correction device 1 according to the present embodiment. First, measured tires 2 are carried one by one from a stock conveyor 10 at an upstream end to a tire identification device 11.
[0016]
In the tire identification device 11, the tire 2 is rotated about the vertical axis, the barcode identification paper stuck to the sidewall of the tire is read by the barcode reader 11a, and the tire information is input.
At the same time, a silicon thin solution is applied to the bead portion of the tire by the lubricant applicator 11b.
Silicon thinning liquid ensures smooth and reliable fitting between the tire and the rim.
[0017]
A distribution device 12 is disposed on the downstream side of the tire identification device 11, and the distribution device 12 tilts the tilting plate 12a on which the tire 2 is placed to the left and right and also tilts forward, so that the tire 2 can be moved in any of the three directions. Can be sorted.
[0018]
When there are two types of tires that are scheduled to be measured, the tire identification device 11 judges the tire information that is input and distributes it to either the left or right side. When it has been done, it is sorted forward.
[0019]
In addition, when measuring only the same type of tires, unreadable or unscheduled tires are assigned to the front and the left and right are assigned alternately.
The tires distributed forward fall on the tilting plate 13a from the dropping port 13, and one of the left and right tilts of the tilting plate 13a causes one of the unreadable barcodes to roll out and the other is unscheduled. Tires are rolling out.
[0020]
The tires distributed from the distribution device 12 to the left and right are conveyed to either one of the left and right parallel transfer conveyors 20 and 20 by the curved roller conveyors 14 and 14 that change the traveling direction to a right angle.
The left and right transfer conveyors 20 and 20 have a symmetric structure with a predetermined gap therebetween, and a part of the rim exchanging device is disposed in the long space between the two.
[0021]
Since the left and right transfer conveyors 20 and 20 are symmetrical, one of them will be described below.
The transfer conveyor 20 is composed of three blocks, a centering block 21, a measurement block 22, and a transfer block 23 in order from the upstream side, and each block is constituted by a roller conveyor.
[0022]
1 and 2, in the centering block 21, a plurality of transport rollers are rotated at a constant speed by a motor 21a, and a pair of stoppers 21b and 21b and centering arms 21c and 21c are provided swingably on the left and right. Then, the tire 2 that has been conveyed is stopped by the stoppers 21b and 21b, and the tire 2 is centered so as to be sandwiched from the left and right by the centering arms 21c and 21c, and then positioned so as to advance a predetermined center position.
[0023]
In the next-stage measurement block 22, a plurality of rollers are rotated at a constant speed by a motor 22a, and the rollers can rotate forward and backward and can also be conveyed upstream.
In this measurement block 22, a pair of left and right positioning arms 22b, 22b are disposed so as to be swingable in a predetermined position in two pairs in the front-rear direction, and the tire is positioned by the four positioning arms 22b.
When the tire 2 is positioned in the measurement block 22 in this way, the central axis oriented in the vertical direction of the tire 2 coincides with the upper and lower rim shafts 25 and 26.
[0024]
The roller of the part which supports the tire 2 in which the measurement block 22 is positioned has a short shaft divided into left and right, and forms a gap in the center part of the tire.
The upper rim shaft 25 is suspended above the gap, the upper rim 3 is detachably attached to the lower end, and the lower rim 4 is detachably attached to the upper end of the lower rim shaft 26 below the same axis. It is attached.
[0025]
The lower rim shaft 26 can be moved up and down, and the lower rim 4 attached to the upper end can penetrate vertically through the gap formed by the short shaft conveying roller.
On the other hand, the upper rim shaft 25 is rotatably supported by a support frame 30 installed between the left and right measurement blocks 22 and 22, and a drive shaft of a servo motor 31 is connected to a portion protruding upward (see FIG. 2, see FIG.
The servo motor 31 is fixedly supported by a support frame 30 installed between the support columns 29 via a bracket.
[0026]
Below the center of the support frame 30 is disposed a rectangular frame 41 that is a holding member that is slidable left and right while being guided by four rails 40 that are laid in the horizontal direction in the horizontal direction. A rotating drum 42 is supported on the rectangular frame 41 by a vertical support shaft 42a.
[0027]
As shown in FIG. 4, the rectangular frame 41 is slidable to the left and right in a posture in which a rectangular shape is formed by the upper and lower side walls and the front and rear side walls, and the left and right sides are opened. It is pivotally supported so as to protrude from the outside.
[0028]
A hydraulic cylinder 43 is suspended from the support frame 30 on the side of the upper side wall of the rectangular frame 41 (see FIG. 3), and the tip of the cylinder rod 43a of the hydraulic cylinder 43 is fixed to the side wall of the rectangular frame 41. As the cylinder rod 43a of the hydraulic cylinder 43 expands and contracts, the rectangular frame body 41 slides left and right together with the rotating drum 42.
The upper and lower side walls of the rectangular frame body 41 are supported by the front and rear side walls, so that sufficient rigidity and strength can be secured structurally and the rotary drum 42 can be pivotally supported.
[0029]
A load cell 45 is provided at the bearing portion of the support shaft 42a that supports the rotating drum 42, and detects the RFV, LFV, etc. of the tire.
A marking device 27 is suspended at a predetermined position above the roller conveyor of the measurement block 22.
[0030]
The measuring block 22 is provided with a pair of symmetrical grinder mechanisms 32 on the opposite side of the rotating drum 42 across the roller conveyor.
The upper grinder mechanism 32 will be described with reference to FIGS. 5 and 6. A swing member 33 is supported by a bracket 29a projecting from a downstream support column 29 via a support shaft 34 so as to be swingable horizontally. The cylinder rod 35a of the servo cylinder 35 pivotally supported by the bracket 29b of the other support column 29 on the other upstream side is pivotally attached to the rocking member 33, and the rocking member 33 is driven by driving the servo cylinder 35. It swings.
[0031]
A motor 36 is provided on the base end side of the swing member 33, and a chain 38 is formed between a sprocket that is supported on the drive shaft of the motor 36 by a grinder 37 pivotally supported on the tip end side and a sprocket integrated with the grinder 37. A grinder 37 provided at the tip of the swing member 33 is rotated by driving the motor 36.
[0032]
The swinging member 33 can be moved up and down somewhat, and the vertical position of the grinder 37 can be adjusted by moving up and down together with the grinder driving mechanism by driving the lifting motor 39.
[0033]
Accordingly, the grinder 37 is set at a required height position with respect to the rotating tire 2 held in the horizontal posture on the upper and lower rims 3 and 4, and the rotating grinder 37 is swung by the servo cylinder 35 to rotate the grinder 37. It is possible to correct the uniformity by cutting the two required locations.
[0034]
The upper grinder mechanism 32 receives the upper half of the horizontally oriented tire 2, and the grinder mechanism 32 provided symmetrically on the lower side receives the lower half of the tire 2. A pair of upper and lower grinder mechanisms 32 is provided on each of the left and right transfer lines.
[0035]
A transport block 23 subsequent to the measurement block 22 in the transfer conveyor 20 is an inclined roller conveyor, and the tire 2 and the like are transported by its own weight.
A stopper 23a which can be moved in and out is provided at a predetermined position near the downstream end.
[0036]
On the downstream side of the above transfer conveyor 20, a distribution conveyor 50 is disposed long in the left-right width direction so as to be continuous with the left and right transfer conveyors 20, 20, and a roller conveyor corresponding to an extension of the left and right transfer conveyors 20, 20 The three-row roller conveyors 51 and 51 and the roller conveyor 52 sandwiched between the roller conveyors 51 and 51 are inclined to convey the tire 2 to the downstream side by its own weight.
[0037]
A plurality of ropes that can be raised and lowered between the rollers of the roller conveyors 51, 52, 51 are stretched across the left and right directions to constitute a rope conveyor 53.
Therefore, if the rope conveyor 53 remains in the lowered state, the tire 2 conveyed from the transfer conveyor 20 is conveyed linearly on the roller conveyor 51, and is unloaded, but when the rope conveyor 53 rises at an appropriate timing, The rope conveyor 53 supports the tire, and therefore the tire 2 can be moved left and right by the rotation of the rope conveyor 53.
[0038]
When the rope conveyor 53 is lowered at a place where it has moved appropriately, it is transferred to one of the roller conveyors 52 and 51, and is carried out by the transferred roller conveyors 52 and 51.
When the rope conveyor 53 moves the tire 2 in either the left or right direction beyond the end, it can be carried out in either the left or right direction.
Therefore, as shown by the arrows in FIG. 1, the tires 2 can be distributed to five places on the distribution conveyor 50 and carried out.
[0039]
The above is the overall schematic structure of the tire uniformity measurement / correction device 1, and the tire uniformity measurement / correction device 1 is provided with a rim replacement device that automatically replaces the rims 3, 4.
[0040]
The tire 2 carried in from the stock conveyor 10 is first identified by reading a barcode in the tire identification device 11, and a silicon thin solution is applied to the bead portion and moved to the distribution device 12, so that the tire cannot be identified. Tires other than the predetermined size are dropped and discharged forward, and the other tires are distributed to the left or right according to the identified size.
In the case where the same type of tire is measured in the right and left measurement blocks, the tires that are carried in may be distributed alternately to the left and right in turn.
[0041]
The distributed tire 2 changes its direction by the curved roller conveyor 14 and enters the centering block 21 of the transfer conveyor 20, is centered by a pair of centering arms 21c and 21c on the left and right, and is measured at a predetermined timing by the stoppers 21b and 21b. Transferred to 22.
[0042]
In the measurement block 22, the tire 2 is positioned by the front, rear, left and right positioning arms 22 a, the lower rim shaft 26 positioned below is raised, and the lower rim 4 mounted at the upper end supports the bead portion of the tire 2 and the tire 2. The upper rim 3 mounted on the upper rim shaft 25 waiting upwards receives the bead portion of the tire 2, the upper and lower rims 3 and 4 are engaged, and the tire 2 has a predetermined height (same as the rotating drum 42). Height).
Then, air is supplied into the tire to obtain a predetermined internal pressure.
[0043]
The hydraulic cylinder 43 is driven to move the rotary drum 42 and press the tire 2 with a predetermined pressure.
By driving one servo motor 31, the predetermined upper rim shaft 25 is rotated to rotate the tire 2.
The rotating drum 42 rotates together.
After the first few rotations, the uniformity measurement correction control is entered.
[0044]
Hereinafter, measurement correction control of RFV, which is the magnitude of the variation in force in the radial direction of the tire, will be described.
When the force RF in the tire radial direction is measured and the change of RF with respect to the number of rotations is represented in a graph, a waveform as shown in FIG. 7 is shown.
The RF rises when the rotary drum 42 is pressed, fluctuates up and down with a predetermined pressing force as a boundary, and forms a waveform with a rotation cycle.
[0045]
FIG. 8 is an enlarged view of this fluctuating waveform portion.
The amplitude of the RF waveform measured by one rotation of the tire is RFV, and is measured every number of rotations.
When the measured RFV is larger than the predetermined target RFV, the grinding is performed by the grinder mechanism, and the top portion of the wave shown by hatching in FIG.
[0046]
The control procedure of the RFV measurement correction control will be described with reference to a flowchart shown in FIG.
After the leveling rotation, first, RFV is measured at the first rotation (step 1), and it is determined from the measured value whether correction is necessary (step 2).
When the measured value of RFV is larger than the target RFV, it is determined that correction is necessary.
[0047]
If correction is unnecessary, this control is terminated.
If it is determined that correction is necessary, the process proceeds to step 3 to determine the cutting depth of grinding by the grinder mechanism, and the measurement correction operation in step 4 is started.
Grinding is performed according to the determined cutting depth, and at the same time, RFV is measured while the rotary drum 42 is pressed.
[0048]
This measurement correction operation is repeatedly executed over 10 rotations of the tire, and 10 RFVs are measured for each rotation.
An example in which measured values of RFV for each number of rotations are plotted is shown in FIG.
In FIG. 10, the horizontal axis represents the number of rotations and the vertical axis represents RFV.
[0049]
Plotting the measured values of 10 RFVs up to 10 times of rotation can roughly analyze the characteristics of the tire for grinding.
Accordingly, when the process proceeds from step 5 to step 6 after 10 revolutions, the rotary drum 42 is separated from the tire 2 and in the next step 7, a regression line is calculated by the least square method based on the measured values of 10 RFVs.
[0050]
As shown in FIG. 10, the regression line represents how much the RFV is reduced by grinding with respect to one revolution of the tire, that is, the correction characteristic of the tire.
In FIG. 10, examples of three tires (1), (2), (3) are displayed, and the example (1) in which the regression line has the largest inclination is a tire having a correction characteristic with a large correction effect. is there.
[0051]
In the next step 8, the correction end rotation number corresponding to the correction end time is predicted from the regression line.
That is, referring to FIG. 10, the point where the regression line intersects with the target RFV is calculated, and the number of rotations in the vicinity of the point is set as the number of rotations for correction completion.
For example, in the case of example (1) in FIG. 10, the number of rotations of 25 can be predicted as the number of correction end rotations.
[0052]
When the correction end rotation frequency is predicted in this way, in step 9, the tire 2 from which the rotary drum 42 has been separated enters a prediction correction operation only for grinding.
The predictive correction work is repeatedly executed until the number of rotations reaches the predicted number of correction end rotations (step 10).
[0053]
Thereafter, the rotating drum 42 is pressed against the tire 2 again (step 11), and RFV is measured for confirmation (step 12).
The RFV measurement should approximate the target RFV.
[0054]
As described above, during the correction of the RFV of the tire 2, the measurement is not always performed by pressing the rotating drum 42 against the tire 2, but a prediction correction in which only correction is performed after the number of rotations exceeds 10 (step 9). Therefore, during the prediction correction, the rotary drum 42 is released away from the tire 2 and can be moved to the other line to be used for measuring the uniformity of other tires.
Therefore, the overall working efficiency of the two-line tire uniformity measurement correction device 1 can be improved.
[0055]
Thus, when the measurement correction of LFV and the like is completed in addition to the measurement correction of RFV, the tire is evaluated as a result of the final confirmation measurement.
Of the uniformity measurements, marks are given by the marking device 27 particularly at the tire points that show the maximum value of RFV.
The marking device 27 is moved to a designated position so that the rotation of the tire 2 is stopped when the tire portion showing the maximum value of RFV by the drive control of the servo motor 31 rotates to a predetermined position (for example, the most downstream side). A mark can be attached.
[0056]
When the measurement is completed, the rotating drum 42 returns to its original state, the internal pressure of the tire 2 is also released, the lower rim shaft 26 is lowered, the tire 2 is placed on the roller of the measurement block 22, and transferred to the transport block 23.
The tire 2 that has transported the rollers of the transport block 23 moves to the sorting conveyor 50, and is discharged from one of the five discharge points in the sorting conveyor 50 according to the evaluation by the uniformity measurement.
[0057]
In the above embodiment, as described above, in the RFV measurement correction control, the measurement correction work is performed for each tire in step 4 of the flowchart of FIG. 9, and the regression line is obtained from the measured values and the prediction correction work is performed. However, when tires of the same type are continuously carried in, the measurement correction work is performed on the first few tires and the regression line data is compared. It is also possible to enter the prediction correction work from the beginning by omitting the measurement correction work by applying to subsequent tires.
[0058]
By doing so, the time required for the rotating drum 42 to be involved in one tire 2 is further shortened, and when necessary, it is possible to immediately move to the necessary line and perform uniformity measurement, further improving work efficiency. Can be achieved.
For tires that require high quality, it is desirable to perform measurement correction work and prediction correction work as a series of work for each tire.
[0059]
Also, when the regression line is calculated from the measurement correction work by the tire, if the slope of the regression line is very small (close to the horizontal), the prediction correction time will be long, so the tire is corrected as a poor quality. Therefore, it is possible to prevent the work efficiency as a whole from being lowered.
[Brief description of the drawings]
FIG. 1 is a plan view in which a part of a tire uniformity measurement correction device according to an embodiment of the present invention is omitted.
FIG. 2 is a side view of the same.
FIG. 3 is a front view seen from the downstream side of the measurement block.
FIG. 4 is a partially omitted perspective view of a measurement block.
FIG. 5 is a side view showing a grinder mechanism.
FIG. 6 is a plan view of the same.
FIG. 7 is a graph showing a change in a radial force RF of a tire with respect to the number of rotations.
FIG. 8 is an enlarged view of the same part.
FIG. 9 is a flowchart showing a control procedure of RFV measurement correction control.
FIG. 10 is a diagram showing a change in a magnitude RFV of a change in the radial force of a tire with respect to the number of rotations.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Tire uniformity measurement correction device, 2 ... Tire, 3 ... Upper rim, 4 ... Lower rim, 5 ... Pallet,
10 ... Stock conveyor, 11 ... Tire identification device, 12 ... Sorting device, 13 ... Drop port, 14 ... Curve roller conveyor,
20 ... Transport conveyor, 21 ... Centering block, 22 ... Measurement block, 23 ... Transport block,
25 ... Upper rim shaft, 26 ... Lower rim shaft, 27 ... Marking device, 29 ... Post,
30 ... support frame, 31 ... servo motor, 32 ... grinder mechanism, 33 ... oscillating member, 34 ... support shaft, 35 ... servo cylinder, 36 ... motor, 37 ... grinder, 38 ... chain, 39 ... lifting motor,
40 ... rail, 41 ... rectangular frame, 42 ... rotating drum, 43 ... hydraulic cylinder, 45 ... load cell,
50 ... sorting conveyor, 51, 52 ... roller conveyor, 53 ... rope conveyor.

Claims (3)

In the tire uniformity measurement correction method in which the force generated when the rotating drum is pressed against the rotating tire supported by the rim shaft and the tire rotates is ground by the grinder mechanism and the uniformity is corrected based on the measurement result.
A measurement correction process that corrects simultaneously while measuring,
A correction characteristic detection step of detecting a correction characteristic of the tire from the correction state in the measurement correction step;
A prediction step of predicting a correction end time from the correction characteristic of the tire detected in the correction characteristic detection step;
A prediction correction step for performing only correction until the correction end time predicted in the prediction step;
A tire uniformity measurement correction method comprising: In the correction characteristic detection step, the characteristic of the change in the measured value by grinding for each rotation of the tire is detected as the correction characteristic of the tire,
2. The tire uniformity measurement and correction method according to claim 1, wherein in the prediction step, a time when the measured value will reach a target value is predicted as a correction end time from the correction characteristics of the tire. In the correction characteristic detection step, a tire correction characteristic is detected for the magnitude of the force variation in the tire radial direction among the tire uniformity components, and in the prediction correction step, the magnitude of the force variation in the tire radial direction is corrected. The tire uniformity measurement correction method according to claim 1 or 2, characterized in that:

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