JP2957108B2 - Tire surface rubber thickness measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates relates to the tire surface rubber thickness measurement <br/> equipment.

[0002]

2. Description of the Related Art In order to manufacture a retreaded tire, it is necessary to cut a tread portion of a steel radial tire worn by running with a buffing machine and use it as a retreaded base tire. Such a process is called a buffing process, and in this process, the outer peripheral length of the base tire is measured by a tire outer peripheral length measuring device in order to know the amount of tread shaving and the like.

[0003] Further, the tire surface rubber thickness (remaining rubber thickness) from the outer peripheral surface of the base tire after buffing to the steel cord inside the tire has a great effect on the performance of the retreaded tire. Have to fit in. Therefore, it is necessary to check the tire surface rubber thickness of the base tire after the buffing. Conventionally, the tire surface rubber thickness has been converted from the outer peripheral length (that is, the outer diameter dimension) of the base tire.

However, in practice, due to the variation in the position of the steel cord, even when the outer peripheral length of the base tire after buffing is within the standard, the tire surface rubber thickness may be inappropriate. Therefore, if necessary, an operator drills holes from the outer peripheral surface of the tire and measures the tire surface rubber thickness to determine whether or not the thickness is within an allowable range.

[0005]

As described above, when the thickness of the rubber on the tire surface is converted from the outer peripheral length of the base tire, there is a case where the actual thickness is deviated from the actual thickness, which is not accurate. When the thickness of the tire surface rubber is measured by performing the above, there is a problem that the operation is inefficient due to the need for manual labor and the buffing process cannot be automated.

Accordingly, the present invention is capable of automatically and accurately measuring the rubber thickness of the tire surface and buffing the base tire with high efficiency and high precision by fully automating the buffing process. and to provide a tire surface rubber thickness measurement equipment possible.

[0007]

To achieve the above object, a tire surface rubber thickness measuring apparatus of the present invention measures a tire surface rubber thickness from an outer peripheral surface of a tire to a steel cord inside the tire. A thickness measurement head portion having the eddy current displacement sensor disposed between a pair of rollers, and moving the thickness measurement head portion closer to the outer peripheral surface of the tire from the radial direction.
Comprising a reciprocal drive means for pressing the freely spaced, the upper
On the outer peripheral surface of the convex arc-shaped cross section of the tire,
Roller outer peripheral surface so that the outer peripheral surfaces of the rollers contact each other.
Are formed in a tapered shape whose diameter is reduced toward the displacement sensor .

[0008] In addition, from the outer peripheral surface of the tire to the inner
To measure the tire surface rubber thickness up to the
An eddy current displacement sensor is arranged between a pair of rollers.
A thickness measuring head portion, and the thickness measuring head portion
To be able to approach / separate from the radial direction
Comprising a reciprocal drive means, and as the outer peripheral surface of the pair of rollers on the outer peripheral surface of convex arcuate cross-sectional shape of the tire is in contact respectively, tapered to the outer peripheral surface of the roller is reduced in diameter to the displacement sensor side And the pair of rollers are rotatable.
A displacement sensor is attached to the support shaft pivotally attached to
The distance between the displacement sensor and the tip surface can be adjusted
It is attached.

Alternatively, from the outer peripheral surface of the tire,
For measuring the tire surface rubber thickness up to the steel cord
Eddy current type displacement sensor is placed between a pair of rollers.
And a thickness measuring head section having the thickness measuring head section.
The outer peripheral surface of the ear is pressed so that it can be freely approached and separated from the radial direction.
Reciprocating driving means for driving the tire,
The outer peripheral surfaces of the pair of rollers are respectively in contact with the outer peripheral surface of the cross-sectional shape.
So that the outer peripheral surface of the roller is reduced in diameter toward the displacement sensor.
A displacement sensor is mounted on a spindle formed in a tapered shape, and the pair of rollers is rotatably pivotally mounted, so that the distance between the outer peripheral surface of the tire and the tip surface of the displacement sensor can be finely adjusted. In addition, the pair of rollers are made of non-metal .

[0010]

With the reciprocating drive means, the thickness measuring head is brought close to the outer peripheral surface of the steel radial tire from the radial direction, and a pair of rollers is pressed against the outer peripheral surface of the tire at a predetermined pressure, thereby forming an eddy current displacement sensor. By approaching the outer peripheral surface, the displacement sensor can quickly and accurately measure the tire surface rubber thickness of the rotating tire.

By forming the outer peripheral surfaces of the pair of rollers in a tapered shape in which the diameter of the pair of rollers is reduced, the contact area between the pair of rollers and the tire is increased and the position of the roller relative to the tire is stabilized. Thus, the distance from the tire outer peripheral surface can be kept constant, and the measurement accuracy of the tire surface rubber thickness is improved.

Further, by mounting the displacement sensor on a support shaft on which a pair of rollers are rotatably pivotally mounted, an error in the mounting position of the displacement sensor with respect to the rollers can be reduced, and the pair of rollers and the displacement sensor can be connected to each other. The measurement head section made of the above can be made compact, and the measurement of the tire surface rubber thickness can be accurately performed. Furthermore, the distance between the tip surface of the displacement sensor and the outer peripheral surface of the tire can be finely adjusted, and by attaching the displacement sensor to the support shaft, the outer peripheral surface of the tire can be adjusted so as not to contact the distal end surface of the displacement sensor. The displacement sensor does not need to be damaged (due to "buffs" on the tire surface after buffing).

[0013] Further, since the pair of rollers is made of a non-metallic material, there is no metal member not to be measured near the eddy current type displacement sensor, and the measurement accuracy is further improved .

[0014]

EXAMPLES hereinafter, to illustrate the invention with reference to the drawings showing an embodiment.

FIGS. 1 and 2 show an embodiment of a tire surface rubber thickness measuring apparatus according to the present invention. This tire surface rubber thickness measuring apparatus includes a displacement sensor 1 provided between a pair of rollers 2 and 2. And a reciprocating drive means 6 for pressing the thickness measuring head 3 against the outer peripheral surface 5 of the retreading base tire 4 so as to be able to freely approach and separate from the radial direction. ing. The measuring device is, for example, (not shown)
Attached to automatic buffing machines, tire rotation drive tables, etc.

The tire 4 is a steel radial tire, and is mounted on a supporting drive base (not shown) so as to be rotatable around an axis L. Reference numeral 7 denotes a fixed gate-shaped frame provided so as to surround the tire 4. The frame 7 is provided with a first cylinder 8 provided with a lock-up unit. 9 is reciprocated in the direction of arrow A (see FIG. 2).

Further, the frame 7 is provided with a first guide member 11 composed of a pair of ball splines 10, 10 and the like, and the intermediate plate 9 is guided by the first guide member 11 so as to be able to linearly reciprocate. A dog mounting bar 12 protrudes from the intermediate plate 9, and a proximity button (dog) 13 is mounted on the mounting bar 12 so as to be adjustable in its axial direction. Reference numeral 31 denotes a proximity sensor for detecting the proximity button metal fitting 13 and stopping the drive of the first cylinder 8 (by operating the lock-up unit).

The intermediate plate 9 is provided with a second cylinder 14 driven by air. The second cylinder 14 reciprocates the thickness measuring head 3 in the direction of arrow B. The second cylinder 14 is attached to the intermediate plate 9 by using an attachment plate 15 or the like. As is clear from FIG. 2, the second cylinder 14 is attached obliquely to the first cylinder 8 and has a wedge-shaped attachment plate.
By changing 15, the inclination angle can be changed.

The thickness measuring head 3 is attached to a mounting member.
Attached to the second guide member 16 formed of a rod of the second cylinder 14, a ball spline, and the like via 19, and is guided so as to be able to reciprocate (linearly) in the direction of arrow B.

The first and second cylinders 8, 14 and the first and second guide members 11, 16 constitute a reciprocating drive means 6. The device according to the present invention is suitable for buffing a tire for rehabilitation, particularly among steel radial tires,
The second guide member 16 and the second cylinder 14 are provided with a cover 17 and a bellows 18, respectively, for buffing the scattered buff powder when buffing the base tire 4 (for this retreading tire). .

As shown in FIGS. 3 and 4, the displacement sensor 1 is provided at the center of the support shaft 20 fixed to the mounting member 19.
The distance E between the outer peripheral surface 5 of the tire 4 and the distal end surface 1a of the displacement sensor 1 can be finely adjusted and attached.

In the illustrated example, the displacement sensor 1 has a threaded portion 1b at its base end, and a female threaded portion formed on the support shaft 20.
An annular screw body 22 is screwed onto the screw 21, and a screw portion 1 b of the displacement sensor 1 is screwed on a female screw portion 22 a formed on the inner peripheral surface of the screw body 22 so as to be able to advance and retreat. Is finely adjustable. Reference numeral 23 denotes a nut for locking the displacement sensor 1, and a cable 25 of the displacement sensor 1 is inserted into the nut 23.

As shown in FIGS. 3, 4 and 5, the displacement sensor 1 uses an eddy current type displacement sensor.
As a result, an eddy current is generated in the metal to be measured (the steel cord 24 inside the tire 4), and the tip surface 1 of the displacement sensor 1 is generated.
The voltage corresponding to the distance from a to the metal to be measured is detected. The detected signal is amplified by the amplifier unit 26 and input to the arithmetic unit 28.

Since the interval E is known, for example, a voltage corresponding to the distance from the tip surface 1a of the displacement sensor 1 to the steel cord 24 is applied to the tire surface rubber from the outer peripheral surface 5 of the base tire 4 to the steel cord 24. By outputting as a voltage converted to the thickness T, the tire surface rubber thickness T
Can be measured. This measurement range is, for example, 0 to 4.5 mm.

Further, for example, as shown in FIG. 5, the tire 4 is rotated and detected by a detector 27 such as an encoder.
The arithmetic unit 28 calculates the output voltage value (or a value obtained by converting the output voltage value into a tire surface rubber thickness T) at each predetermined pitch in the circumferential direction of the tire 4 while detecting the rotational position of the tire 4. Are displayed or recorded on the output device 29. In this way, the tire surface rubber thickness T is set at a predetermined pitch in the circumferential direction of the tire 4 {for example, about 180
Can be measured at ~ 250 points───. Of course, it is also possible to detect and display or describe the rubber thickness T continuously over the entire circumference of the tire 4.

Further, as shown in FIG.
Are rotatably connected to both ends of the support shaft 20 by bearings 30 so as to be rotatable in the circumferential direction of the base tire 4. By the way, since the outer peripheral surface 5 of the tire 4 has a convex arc-shaped cross-sectional shape as shown in the figure, if the outer diameter of the roller 2 is the same in the axial direction, the outer peripheral surface 5 of the tire 4 and the roller 2 The rollers 2 and 2 become unstable due to contact with the corners, and it becomes difficult to keep the distance (interval E) between the tire 4 and the displacement sensor 1 constant.

Therefore, in the present invention, the outer peripheral surface 5 of the tire 4 is
The outer peripheral surfaces 2a, 2a are formed in a tapered shape in which the diameter is reduced toward the displacement sensor 1 in accordance with the radius of curvature R of the tire 4, so that the contact area between the tire 4 and the rollers 2, 2 is increased, and the tire 4 and the displacement sensor 1, while keeping the distance from the tire constant, accurate measurement of the tire surface rubber thickness T is possible. The taper angle of the outer peripheral surface 2a of the roller 2 is, for example, about 2.5 to 4.0 deg.

When the width of the roller 2 is large, the difference in the rotational speed between the two ends of the roller 2 caused by the difference in the outer peripheral length of the base tire 4 becomes large, making it difficult for the roller 2 to roll smoothly. Therefore, the pressing force of the second cylinder 14 is adjusted so that the roller 2 rolls smoothly, and the width of the roller 2 is set to an appropriate size.

Since the metal member which is not to be measured must be separated from the side surface of the displacement sensor 1 by a predetermined distance so as not to adversely affect the measurement accuracy of the displacement sensor 1, the metal member is disposed on the side of the displacement sensor 1. Rollers 2 and 2 are made of nonmetal such as synthetic resin.

However, when the measuring device of the present invention is used for measuring the surface rubber thickness T of the base tire in the retreading tire buffing step, after the buffing of the outer peripheral surface 5 of the base tire 4, the illustration is omitted. Is controlled in parallel with the operation of the tire circumference measuring device. Therefore, even if the tire surface rubber thickness is measured, the cycle time of the buffing process including the measurement of the tire outer peripheral length does not increase.

Next, a method of measuring the tire surface rubber thickness by using the measuring device configured as described above will be described.

First, as shown in FIGS. 1 and 2, after buffing the outer peripheral surface 5 of the base tire 4, the first cylinder 8 is driven in the extension direction, and the intermediate plate 9 is moved to a predetermined position near the base tire 4. When it reaches the position, the proximity button 31
Is detected, the lock-up unit of the first cylinder 8 operates, and the intermediate plate 9 stops. Next, the second cylinder 14 is driven in the extension direction, the thickness measuring head unit 3 approaches the base tire 4, and the rollers 2 are pressed against the outer peripheral surface 5 of the base tire 4 with a predetermined pressure.

Here, irrespective of the outer peripheral length of the base tire 4 after the buffing, the mounting position of the proximity button 13 and the displacement button 1 are set so that the displacement sensor 1 approaches the outer peripheral surface 5 of the base tire 4 from the radial direction. The angle of attachment of the second cylinder 14 to the intermediate plate 9 is adjusted in advance. Further, the position of the displacement sensor 1 (that is, the position shown in FIG. 3) is set such that the "buff" remaining on the outer peripheral surface 5 of the base tire 4 does not damage the tip end surface 1a of the displacement sensor 1 when the tire surface rubber thickness is measured. Interval E)
Is adjusted in advance.

The base tire 4 at the time of measuring the tire outer peripheral length
With the rotation, the tire surface rubber thickness T is measured by the displacement sensor 1 at a predetermined pitch in the circumferential direction of the base tire 4 or continuously in the circumferential direction. It is determined whether or not the tire surface rubber thickness T measured in this manner is within an allowable range as the rehabilitation base tire 4 (that is, whether or not it can be used).

Next, another method for measuring the tire surface rubber thickness will be described.

In this case, during the buffing step of the outer peripheral surface 5 of the base tire 4, the thickness measuring head 3 is brought close to the rotating base tire 4, and the tire surface rubber thickness is increased in the same manner as described above. Measure T. At this time, it is desirable that the measurement of the tire outer circumference be simultaneously advanced (to reduce the cycle time).

Then, the measured tire surface rubber thickness T
The remaining amount to be buffed is detected based on (or both the tire outer peripheral length and the tire surface rubber thickness T), and the remaining amount is buffed.

It should be noted that the present invention is not limited to the above-described embodiment, and the design can be freely changed without departing from the gist of the present invention. For example, in order to specify the circumferential position of the tire 4, it is also preferable to attach an index mark in the circumferential direction of the tire 4, detect the mark with a detector, and perform a composite operation with the signal from the displacement sensor 1. .

The outer peripheral surfaces 2a, 2a of the rollers 2, 2
May be formed so that the outer peripheral surface 2a is tapered along the outer peripheral surface 5 of the base tire 4 to be in contact therewith.

[0040]

Since the present invention is configured as described above, the following significant effects can be obtained.

According to the tire surface rubber thickness measuring device of the first , second and third aspects, the eddy current displacement sensor 1 and the reciprocating drive means 6 are used to measure the distance from the outer peripheral surface 5 of the tire 4 to the steel cord 24. The tire surface rubber thickness T can be measured quickly and accurately, and this contributes greatly to realizing, for example, automation of buffing of a retreading base tire.

The outer peripheral surfaces 2a of the pair of rollers 2, 2
2a is formed in a tapered shape to reduce the diameter toward the displacement sensor 1 side.
Therefore, the contact area between the outer peripheral surface 5 of the tire 4 and the outer peripheral surfaces 2a, 2a of the pair of rollers 2, 2 can be increased, and the displacement sensor 1 is maintained in a stable state. Since the distance from the tire 4 is kept constant, the tire surface rubber thickness T can be accurately measured.

[0043] According to claim 2, 3 tire surface rubber thickness measuring device according displacement sensor 1 is maintained in a stable state, small error in the position of the displacement sensor 1 against rollers 2,2, the tire surface rubber The thickness T can be measured with higher accuracy. Further, the distance E between the two surfaces 1a and 5 can be freely adjusted so that the front end surface 1a of the displacement sensor 1 does not contact the outer peripheral surface 5 of the tire 4, so that the occurrence of breakage of the displacement sensor 1 due to the contact is effective. Can be prevented. Further, the measuring head unit 3 becomes compact.

According to the tire surface rubber thickness measuring device of the third aspect , since the pair of rollers 2 and 2 are made of non-metal, the measurement accuracy of the displacement sensor 1 is not adversely affected, and the tire is accurately measured. The surface rubber thickness T can be measured .

[Brief description of the drawings]

FIG. 1 is a front view showing one embodiment of the present invention.

FIG. 2 is a side view.

FIG. 3 is a plan view of a thickness measuring head part, which is partially cut away.

FIG. 4 is a front view of a thickness measuring head portion partially cut away.

FIG. 5 is a block diagram.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Displacement sensor 1a Tip surface 2 Roller 2a Outer peripheral surface 3 Thickness measuring head part 4 Tire 5 Outer peripheral surface 6 Reciprocating drive means 20 Support shaft 24 Steel cord T Tire surface rubber thickness E Interval

──────────────────────────────────────────────────続 き Continuation of the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) G01B 7/00-7/34 G01B 21/00-21/32

Claims (3)

(57) [Claims] An eddy current displacement sensor for measuring a tire surface rubber thickness from an outer peripheral surface of a tire to a steel cord therein is disposed between a pair of rollers. comprising a thickness measuring head 3 comprising Te, and reciprocally driving means 6 for pressing the said thickness measuring head 3 as a universal approach and away from the radial direction to the outer peripheral surface 5 of the tire 4, and the
On the outer peripheral surface 5 of the convex arc-shaped cross section of the tire 4,
So that the outer peripheral surfaces 2a of the rollers 2 are in contact with each other,
The outer peripheral surface 2a of the roller 2 is reduced in diameter toward the displacement sensor 1 side.
A tire surface rubber thickness measuring device formed in a tapered shape . 2. An outer peripheral surface 5 of a tire 4 and a steel inside thereof.
To measure the tire surface rubber thickness T up to
Between the pair of rollers 2 and 2
A thickness measuring head portion 3 disposed therein, and the thickness measuring head 3
The part 3 approaches and separates from the outer peripheral surface 5 of the tire 4 in the radial direction.
A reciprocating drive means 6 for pressing the movable comprises, as the outer peripheral surface 2a of the outer surface 5 to the pair of rollers 2,2 of convex arcuate cross-sectional shape of the <br/> tire 4, 2a are in contact with each ,
An outer peripheral surface 2a of the roller 2 is formed in a tapered shape having a diameter reduced toward the displacement sensor 1 , and the pair of rollers 2
The displacement sensor 1 is mounted on a support shaft 20 that is rotatably pivoted.
E between the outer peripheral surface 5 of the actuator 4 and the distal end surface 1a of the displacement sensor 1.
A tire surface rubber thickness measuring device , characterized in that it can be finely adjusted and attached . 3. An outer peripheral surface 5 of a tire 4 to a steel inside thereof.
To measure the tire surface rubber thickness T up to
Between the pair of rollers 2 and 2
A thickness measuring head portion 3 disposed therein, and the thickness measuring head 3
The part 3 approaches and separates from the outer peripheral surface 5 of the tire 4 in the radial direction.
And reciprocating drive means 6 for freely pressing.
On the outer peripheral surface 5 of the convex arc-shaped cross section of the tire 4,
So that the outer peripheral surfaces 2a of the rollers 2 are in contact with each other,
The outer peripheral surface 2a of the roller 2 is reduced in diameter toward the displacement sensor 1 side.
The displacement sensor 1 is connected to the outer peripheral surface 5 of the tire 4 and the tip end surface 1a of the displacement sensor 1 on a support shaft 20 which is formed in a tapered shape and on which the pair of rollers 2 and 2 are rotatably connected. Interval E
As lifting tweak, mounting Rutotomoni, the pair of rows
A tire surface rubber thickness measuring device, wherein the rubbers 2 and 2 are made of nonmetal .