JPH06126857A - Device and method for cutting and finishing tire surface - Google Patents

Abstract

PURPOSE:To cut tire surface in a short time to give a high quality finish thereto. CONSTITUTION:A tire 22 is set on a tire rotating part 12 of a tire surface cutting and finishing device 10 and is rotated on its axis at a speed of predetermined revolutions. At the same time, a belt type grinder 74 is positioned at a teaching point of the surface of the tire by a head 64 provided at the end of an arm 62 of a robot 54 and is pressed against the tire surface with a predetermined pressing force to cut it. Upon (1+alpha) rotation of the tire 22, a motor 24 for rotating the tire is deenergized to stop the rotation of the tire 22, a rotating block 70 is then raised along the vertical guide of a vertical block 68 to lift the belt type grinder 74 off the tire 22 and the grinder is repositioned at the next teaching point.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire surface cutting and finishing apparatus and a tire surface cutting and finishing method which are used for correcting the uniformity of tires.

[0002]

2. Description of the Related Art Conventionally, a new studless tire uses foam rubber, but a thin skin (about 1 mm) without a foamed surface is formed on the tire surface, and it is desirable to remove this thin skin. Air bubbles are not exposed on the tire surface, and the performance as a studless tire cannot be exhibited 100%. Therefore, it is necessary to cut this thin skin. Further, since it is necessary to cut the thin skin without changing the RR and RFV of the tire, conventionally, a studless tire was attached to an actual vehicle and the thin skin was removed by actual running.

However, the cutting of the thin skin by this actual vehicle has a problem that it takes time and fuel cost and the thin skin cannot be completely cut unless the traveling distance is sufficient.

Further, conventionally, after the uniformity of the tire is corrected with a grinder, a cutting mark is formed on the tire surface as a step difference of about 1 mm.
In the case where this step difference is polished and corrected without changing the FV, the operator grinds the tire surface using a belt-type grinder.

However, with this method, fine powder is generated during polishing, which creates an unfavorable environment for the operator, and there are drawbacks such as variations in finish quality and working time due to differences in the skill of the operator.

[0006] Conventionally, spews formed on the tire surface during vulcanization molding have been cut with a pawl machine. However, some uncut material is left. Therefore, the operator leaves the uncut material smooth with a buffing machine. It was

However, even in this case, fine powder is generated during polishing, which creates an unfavorable environment for the operator, and there are problems such as variations in finish quality and working time due to differences in the skill of the operator.

[0008]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention has an object to obtain a tire surface cutting and finishing apparatus and a tire surface cutting and finishing method capable of performing high quality tire surface cutting and finishing in a short time. is there.

[0009]

A tire surface cutting and finishing apparatus of the present invention according to claim 1 is a tire rotating means for rotating a tire around a tire axis, a belt type grinder for cutting the tire surface, and this belt type. Belt grinder support means for sequentially positioning the grinder at a predetermined position on the tire surface and pressing the belt grinder against the tire surface with a predetermined pressing force.

Further, the tire surface cutting and finishing method of the present invention according to claim 2 is a tire surface cutting and finishing method in which a belt type grinder is pressed against the surface of a tire rotating around a tire axis to finish the tire surface. And a cutting start step of automatically positioning and pressing the belt grinder at the cutting start position on the circumference of the rotating tire to start cutting, and a cutting for cutting a predetermined area along the circumference of the tire with the belt grinder. It is characterized by including a step and a cutting end step of automatically separating the belt grinder from the tire at a point on the tire circumference that avoids the cutting start position after the cutting step.

Further, the tire surface cutting and finishing method of the present invention according to claim 3 is the tire surface cutting and finishing method of the present invention according to claim 2, wherein a belt grinder is pressed against the surface of the tire during the cutting step. Pressing force is 2
It is characterized in that it is set to 00g to 400g.

[0012]

In the tire surface cutting and finishing apparatus according to the first aspect of the invention, the tire is mounted on the tire rotating means, and the tire is rotated around the axis at a predetermined rotation speed. At the same time, the belt grinder supporting means positions the belt grinder at a predetermined position on the tire surface and presses it with a predetermined pressing force to operate the belt grinder to cut the tire surface.

Next, when the cutting of a predetermined area on the tire surface is completed, the belt grinder supporting means moves the belt type grinder to the next predetermined position on the tire surface and presses it with a predetermined pressing force. To cut the tire surface.

By repeating this, the entire tire surface is cut. Therefore, in the tire surface cutting and finishing apparatus of the present invention,
Compared with the conventional tire surface cutting and finishing performed by the operator using the belt grinder, the tire surface cutting and finishing can be performed in high quality in a short time.

In the tire surface cutting and finishing method according to the present invention, first, in the cutting starting step, the belt surface grinder is pressed against the surface of the tire rotating around the axis to finish the cutting of the tire surface. In this case, the belt grinder is automatically positioned at the starting position on the circumference of the rotating tire and is pressed with a predetermined pressing force.

Next, in a cutting step, a predetermined area along the circumference of the tire is cut. Next, in the cutting end step, the belt grinder is automatically separated from the tire at a point on the tire circumference that avoids the cutting start position.

By repeating this, the entire tire surface is cut. Therefore, in the tire surface cutting and finishing method of the present invention,
Compared with the conventional tire surface cutting and finishing performed by the operator using the belt grinder, the tire surface cutting and finishing can be performed in high quality in a short time.

Further, in the tire surface cutting and finishing method of the present invention according to claim 3, in the tire surface cutting and finishing method of the present invention according to claim 2, a belt grinder that is pressed against the surface of the tire during the cutting step is pressed. 20 pressure
It was set to 0 g to 400 g. This is because if the pressing force is more than 400 g, the rotation speed of the belt or the tire of the belt grinder becomes slower, or it may stop rotating and excessive cutting may occur, and if the pressing force is less than 200 g, the tire surface Since the belt surface of the belt grinder does not adhere to the circumferential or radial curvature surface that it has, only the part protruding from the tire surface can be cut, and when there is a large radius variation on the tire circumference, a large radius part This is because only uneven cutting can occur, and uneven cutting occurs on the tire circumference.

[0019]

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

As shown in FIG. 2, the tire rotating portion 12 as the tire rotating means of the tire surface cutting and finishing apparatus 10 of this embodiment has a left side wall 14 and a right side wall 16 which are parallel to each other.
Is equipped with. A right rim 20 having a sprocket 18 mounted thereon is rotatably supported on the right side wall 16,
An air passage (not shown) for supplying and filling air into a tire 22 described later is formed in the right rim 20.

A sprocket 26 is fixed to the output shaft of a tire rotation motor 24 fixed to the lower end of the right side wall 16, and a chain 28 is stretched between the sprocket 18 and the sprocket 26. .

A screw shaft 32 having a screw formed on the outer periphery of the rear end is screwed into a screw block 30 fixed to the left side wall 14 facing the right rim 20.
The sprocket 34 splined to the tip of
The left side wall 14 is rotatably supported.

A movable member 36 is attached to the tip of the screw shaft 32.
Is rotatably connected, and a guide rod 40 penetrating a guide block 38 fixed to the left side wall 14 is fixed to the movable body 36.

A sprocket 44 is fixed to the output shaft of the tire clamping motor 42 fixed to the lower end of the left side wall 14, and a chain 46 is stretched between the sprocket 34 and the sprocket 44. .

A left side rim 48 facing the right side rim 20 is rotatably supported by the movable body 36. The left side rim 48 and the right side rim 20 sandwich the tire 22 from both sides, and the tire 22 is held. It is designed to rotate around the tire axis.

A cylinder 50 is vertically fixed to the bottom of the tire rotating portion 12. At the tip of the piston rod of the cylinder 50, the tire stand 5 on which the tire 22 is placed is mounted.
2 is fixed, and a guide rod is attached to the tire stand 52.

As shown in FIG. 1, the robot 5 is provided near the tire rotating portion 12 of the tire surface cutting and finishing device 10.
4 are arranged. The robot 54 operates based on a signal from a controller (not shown).

The robot 54 has a base 56, and a body 60 is vertically movable (in the direction of arrow A in FIG. 1) via a bellows 58 on the base 56, and a rotation axis B is provided.
Is rotatably supported in the direction of arrow C with the axis as the axis.
An arm 62 is slidably supported by the body 60 in the direction of arrow D, and the arm 62 can project from the body 60 or retract into the body 60. A head 64 as a belt-type grinder supporting means is supported at the tip of the arm 62.

As shown in FIG. 3, the head 64 is provided with a horizontal block 66 extending in the horizontal direction and a vertical block 68 extending in the vertical direction. The vertical block 68 is driven by a driving means (not shown). It is movable in the horizontal direction (the direction of arrow X in FIG. 3) along the horizontal guide 66A formed on. The vertical block 68 has a vertical guide 6 in the vertical direction (direction of arrow Z in FIG. 3).
8A is formed, and a rotation block 70 is supported on the vertical guide 68A so as to be movable in the vertical direction (direction of arrow Z in FIG. 3) by a driving unit (not shown). A well-known belt-type grinder 74 is supported on the rotating block 70 via an L-shaped bracket 72, and can be oscillated in an arc shape in the direction of arrow R in FIG. 3 by a driving means (not shown). ing.

The belt type grinder 74 has a drive shaft 76.
In the present embodiment, a cutting belt 80 having a width of 30 mm is stretched between the driven shaft 78 and the driven shaft 78, and the cutting belt 80 presses the outer peripheral surface of the tire 22 with a pressing force F (200 g to 400 g).
While contacting with each other, it rotates in the direction of arrow L in FIG.

Next, the operation of this embodiment will be described. First,
The tire 22 whose surface is to be cut is placed upright on the tire stand 52. Next, the cylinder 50 is operated to operate the tire 2
2 is raised so that the axis line of the tire 22 and the axis line of the right rim 20 are aligned with each other.

Next, the motor 42 is operated to operate the left rim 4
8 is brought closer to the right rim 20, and the tire 22 is sandwiched from both sides by the left rim 48 and the right rim 20.

Next, air is supplied and filled into the tire 22 from the air passage of the right rim 20. Next, the robot 54 is operated to apply the belt grinder 74 with a constant pressing force (200 g to 400 g) to the teaching point (P1 in FIG. 4) of the tire 22, which is previously taught to the robot 54. Contact (cutting start process).

In this case, the belt type grinder 74 located approximately 2 cm above the tire 22 starts descending toward the tire 22, and at the same time, the tire rotating motor 24 is operated to rotate the tire 22 to rotate the belt type grinder 74. In the same direction (direction of arrow L in FIG. 4) (direction of arrow W in FIG. 4) (the surface speed of the tire 22 is 2 m / min to 1).
0m / min, surface speed of belt type grinder 74 is 180
m / min).

As a result, a predetermined area along the circumference of the tire 22 is cut by the belt grinder 74 (cutting step).

Next, when the tire 22 rotates by (1 + α), the tire rotation motor 24 is stopped, and the tire 22 is rotated.
Simultaneously with the stop of the rotation, the rotating block 70 is raised along the vertical guide 68A of the vertical block 68, and the belt type grinder 74 is separated from the tire 22 (cutting finishing step).

In this case, as shown in FIG. 4, the rotation angle α
Is a value obtained by dividing the tire circumference by the number N of teaching points, and the RR (RVF) value does not change before and after the finishing of the belt grinder by distributing the cutting start points, which tend to be overcut in general. I am trying.

Next, the vertical block 68 and the horizontal block 6
6 along with the horizontal guide 66A, and as shown in FIG. 5, the belt grinder 74 is moved in the width direction of the tire 22 (direction of arrow V in FIG. 5) to advance the robot 5 in advance.
Next teaching point P that was taught in 4
Stop above 2. In this case, the belt type grinder 74 is moved in the width direction of the tire 22, and the bracket 72 is swung by the rotating block 70.
The belt type grinder 74 has a teaching point (see FIG. 4).
So that it is parallel to the cutting surface of P2).

Next, the rotation block 70 is moved to the vertical block 6
8 vertical guide 68A to lower the belt type grinder 74 to a constant pressing force (200 g to 400 g)
Then, the robot 54 is brought into contact with the next teaching point P2 which is previously taught to the robot 54 (cutting start step).

By repeating this, the entire circumference of the tire 22 is cut. In addition, when cutting the entire width of the tire 22 as when removing the thin skin of the tire 22, for example, when the tire width is 200 mm, the teaching points are about 20 places (increase or decrease depending on the width of the tire) and the width Using the belt type grinder 74 of 30mm, the belt type grinder 74
Is moved in the tire width direction in units of about 10 mm at the center of the belt width, and is overlapped for cutting.

When the tire 22 has a spew (height of about 2 mm), the spew on the entire circumference of the tire is removed at the first time and the entire circumference of the tire is cut at the second time, so that each teaching of the second time is performed. The point is the position where the belt grinder 74 is closer to the tire by about 1 mm from the first teaching point.

In addition, the tire 2 is used as when finishing the stepped portion made by the uniform grinder work smoothly.
When a part of 2 is cut, for example, as shown in FIG. 6, there are 5 teaching points on each side (increase or decrease depending on the width to be cut), and a belt type grinder 74 with a width of 30 mm is used. The formula grinder 74 is moved in the tire width direction in units of 5 mm to 10 mm.

Further, in this embodiment, the belt grinder 74 which is pressed against the surface of the tire 22 during the cutting process.
Since the pressing force F of the tire is set to 200 g to 400 g, the elasticity of the belt 80 of the belt grinder 74 causes the tire 2
The belt 80 is evenly fitted to the concave and convex portions of 2,
The tire 22 can be cut without changing the RR and RVF. As shown in FIG. 3, the known belt type grinder 74 has a pad 81 mounted inside the belt 80.
Since the elasticity of 0 cannot be used, the pad 81 is removed and used.

If the pressing force F exceeds 400 g, the rotation of the belt 80 of the belt type grinder 74 or the tire 22 may be slowed or stopped, and excessive cutting may occur. On the other hand, when the pressing force F is less than 200 g, the surface of the belt 80 of the belt grinder 74 does not come into close contact with the circumferential or radial curvature surface of the tire surface, so that only the portion protruding from the tire surface can be cut. Further, when there is a large variation in the radius on the tire circumference, cutting can be performed only on the area with a large radius, resulting in uneven cutting on the tire circumference.

As described above, in the present embodiment, the surface cutting and finishing of the tire, which has been performed by the actual vehicle running or the operator using the belt grinder 74, can be automated, and the important performance of the tire such as RV and RFV. Surface cutting finishing can be performed in a short time without changing the above. In addition, since spews can be removed from the root without damaging the tire, the appearance of the tire can be improved and the commercial value of the tire can be increased.

In the above embodiment, the tire 22 is rotated in the direction of rotation of the belt grinder 74 (direction of arrow L in FIG. 4).
Although the tire 22 is rotated in the same direction (direction of arrow W in FIG. 4), the tire 22 may be rotated in a direction opposite to the direction of rotation of the belt grinder 74 (direction of arrow L in FIG. 4).

(Test Example) In the tire surface cutting and finishing apparatus of this embodiment, five tires were cut and finished with the teaching point being 10 points, and the RVF before and after the cutting was performed.
And the results are shown in Table 1. In addition, it is preferable that the RVF increase amount in Table 1 has a small absolute value.

[0048]

[Table 1]

From the results shown in Table 1, it was clarified that the present invention is excellent because the RVF of the tire hardly changed before and after the finishing of cutting the tire surface.

[0050]

The tire surface cutting and finishing apparatus and the tire surface cutting and finishing method of the present invention have the above-mentioned constructions and methods, and therefore have an excellent effect that the tire surface cutting and finishing can be performed with high quality in a short time. .

[Brief description of drawings]

FIG. 1 is a side view showing a tire surface cutting and finishing apparatus according to an embodiment of the present invention.

FIG. 2 is a front view showing a tire surface cutting and finishing apparatus according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a head of a tire surface cutting and finishing apparatus according to an embodiment of the present invention.

FIG. 4 is a schematic view showing a teaching point of a tire surface cutting and finishing method according to an embodiment of the present invention as viewed from the tire axial direction.

FIG. 5 is a cross-sectional view taken along the tire axis showing the teaching points of the tire surface cutting and finishing method according to one embodiment of the present invention.

FIG. 6 is a cross-sectional view taken along the tire axis showing the teaching points of a tire surface cutting and finishing method according to another embodiment of the present invention.

[Explanation of symbols]

 10 Tire Surface Cutting and Finishing Device 12 Tire Rotating Part 22 Tire 24 Tire Rotating Motor 42 Tire Holding Motor 50 Cylinder 52 Tire Stand 54 Robot 60 Body 62 Arm 64 Head 66 Horizontal Block 68 Vertical Block 70 Rotating Block 74 Belt Grinder 80 Cutting belt

Claims (3)

[Claims] 1. A tire rotating means for rotating a tire around a tire axis, a belt grinder for cutting the tire surface, a belt grinder which is sequentially positioned at a predetermined position on the tire surface, and the belt grinder is used for the tire surface. And a belt type grinder supporting means for pressing the belt surface with a predetermined pressing force. 2. A tire surface cutting and finishing method in which a belt type grinder is pressed against the surface of a tire rotating around a tire axis to finish the cutting of the tire surface, wherein cutting of the belt type grinder on the circumference of the tire is started. A cutting start step of automatically positioning and pressing at a position to start cutting, a cutting step of cutting a predetermined area along the circumference of the tire with a belt grinder, and a tire avoiding the cutting start position after this cutting step And a finishing step of automatically separating the belt grinder from the tire at a point on the circumference. 3. The pressing force of a belt grinder that is pressed against the surface of the tire during the cutting step is 200 g to 4 g.
The tire surface cutting and finishing method according to claim 2, wherein the method is 100 g.