KR20140136153A - Method and Apparatus of Post Cure Inflation for Tire - Google Patents

Abstract

The present invention relates to a tire PCI method and apparatus for preventing shrinkage of a nylon cord by slowly cooling the green case while maintaining the air pressure after vulcanization,
The vulcanization is completed and a high pressure is applied to the inside of the tire 10 mounted on the PCI rim 11 in comparison with the normal PCI pressure for a predetermined period of time so that the tire 10 is accurately seated in the PCI rim 11 So that the tire 10 is cooled while keeping the internal pressure of the tire 10 at a normal pressure of the PCI.
As a result, the PCI operation proceeds with the vulcanized tire mounted correctly in the PCI rim, thereby reducing the unity defect of the finished product tire.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a tire PCI method and apparatus for preventing shrinkage of a nylon cord by slowly cooling the green case after vulcanizing and maintaining the air pressure. More particularly, the present invention relates to a tire PCI method and device, To thereby prevent the unfavorableness of the finished product tire due to the incorrect installation of the tire.

In general, tires are manufactured by refining process that mixes various raw materials to make compound, semi-finished products that make semi-finished products of tread, belt semi-finished products and inner liner semi-finished products in sheet form by extrusion, rolling and cutting A manufacturing process, a molding process in which the semi-finished products are attached to a molding drum and molded into a green case, and a vulcanization process in which a green case separated from the molding drum is vulcanized to produce an article tire.

The vulcanization step refers to a step of putting a green case completed in a molding step into a mold of a vulcanizer and then applying heat and pressure steam from inside and outside to obtain a unique tread of the tire. The mold used in this vulcanization process is mainly composed of an upper mold and a lower mold having a plurality of sections gathered. Inside the mold, a green case and a bladder contacting the inside of the green case are built in have.

In fact, in the vulcanization process, a high-temperature, high-pressure gas is supplied to the bladder to expand the bladder, and the expanded bladder pushes the green case to the mold side. As a result, the green case expands and the outer circumferential surface of the green case contacts the mold to form a tread.

On the other hand, since the vulcanized tire is in a high temperature state, the nylon cord may be shrunk during cooling in the air, resulting in deterioration of tire uniformity and appearance quality. Thus, the nylon cords of the tire are not shrunk by blowing air inside the vulcanized tire and keeping it in a state of being inflated for a predetermined period of time. The apparatus for carrying out such a PCI process is called a tire PCI device do.

A conventional tire PCI device is provided at the rear end of a vulcanizer. The conventional tire PCI device includes a conveyor for conveying a vulcanized tire from a vulcanizer, a PCI rim to which a bead portion of the conveyed tire is coupled, And a pressure supply unit for maintaining a constant pressure.

In the conventional tire PCI device, after the vulcanized tire is mounted on the PCI rim, pressure is supplied from a pressure feeder to cool the tire for about 20 minutes while maintaining the internal pressure of the tire at 1.5 to 2.5 kgf / Of the nylon cord of the tire can be caused to shrink.

However, in the conventional tire PCI device, the internal pressure of the tire is kept constant, but when the tire is erroneously mounted on the PCI rim, the internal pressure of the tire changes due to the pressure loss, so that the nylon cord is partially contracted, There is a problem in that the uniformity performance of the semiconductor device is deteriorated.

On the other hand, Patent Document 1 discloses an apparatus and method for expanding and cooling a tire by supplying a compressed fluid in a state in which a vulcanized tire is held tightly.

Patent Document 2 describes a vulcanizer having a transport mechanism for transporting a vulcanized tire to a PCI,

Patent Document 3 discloses a technique of measuring the radial run out (RR) of a vulcanized tire and changing the angle between the rim holders according to the angular displacement of the rim holder corresponding to the corresponding RR, thereby adjusting the uniformity of the tire at low cost Discloses a method and apparatus for adjusting the uniformity of pneumatic tires.

Patent Document 4 discloses a technique for minimizing the deformation of a tire by rotating a vulcanized tire while performing a PCI process and reducing a defective rate by removing a step formed on an outer surface of the tire during a vulcanization process of a green tire in a PCI process A method and apparatus for improving the uniformity of a tire are disclosed.

KR 10-1992-0007786 A JP 2004-050456 A JP 2008-137286 A KR 10-2010-0025231 A

In order to solve the above-mentioned conventional problems, the present invention provides a method for improving the mounting accuracy of tires by controlling the high-pressure and low-pressure two-step control when the vulcanized tire is mounted on the PCI rim, The present invention is directed to a tire PCI method and apparatus capable of preventing a tire from being damaged.

In order to accomplish the above object, the present invention provides a tire PCI method in which a vulcanized tire is maintained in a state where a pressure higher than a normal PCI pressure is applied to a tire mounted on a PCI rim for a predetermined time, And a second step of allowing the tire to cool while keeping the internal pressure of the tire at the normal PCI pressure when the first step is completed.

According to the tire PCI method of the present invention, in the first step, the pressure is applied so as to reach a pressure of 5.0 kgf / cm 2 within 25 seconds and maintained for 10 seconds, and in the second step, the internal pressure of the tire is reduced to 1.5 And a pressure of about 2.5 kgf / cm < 2 >.

Further, according to the tire PCI method of the present invention, the arrival time of the pressure of 5.0 kgf / cm 2 in the first step is 6 to 14 seconds.

The tire PCI device of the present invention includes a PCI rim on which a vulcanized tire is mounted; A pressure supplier for providing pressure to maintain the tire in an expanded state; A pressure pipe connecting the tire and the pressure supply to provide a PCI pressure; A proportional control valve which is adjustable in pressure to control the PCI pressure at a high pressure and a low pressure and is installed at one side of the pressure pipe; And a computer for transmitting and receiving a control signal to and from the AD converter of the proportional control valve and controlling the proportional control valve by a pressure control program.

According to the tire PCI device of the present invention, a pressure regulator is additionally provided between the proportional control valve and the tire so that the pressure of the PCI can be increased and the high pressure can be instantaneously applied to the tire.

Further, according to the tire PCI device of the present invention, the diameter of the pressure pipe is 20 mm.

In the tire PCI method and apparatus of the present invention, when a vulcanized tire is mounted on a PCI rim and a momentary high pressure is applied, the tire is correctly mounted on the PCI rim, and then the PCI process is performed with a normal PCI pressure The uni-formability of the finished product tire is improved.

According to the tire PCI method and apparatus of the present invention, when the high pressure is applied to the tire, the pressure is increased by the pressure regulator and supplied, so that the pressure inside the tire rapidly increases, shortening the time required for the tire to be correctly mounted on the PCI rim have.

Further, according to the tire PCI method and apparatus of the present invention, a 20 mm diameter pipe is used instead of the conventional 15 mm diameter pipe as the pressure pipe for supplying pressure to the tire, thereby shortening the target pressure reaching time, Is installed in the PCI rim, it is possible to improve the performance of the finished tire of the PCI process.

1 is a process diagram showing a tire PCI method according to the present invention.
2 is a block diagram showing a tire PCI device according to the present invention.
3 is a graph comparing changes in tire internal pressure of the conventional PCI method and the PCI method of the present invention.

Hereinafter, a tire PCI method and apparatus of the present invention will be described with reference to the accompanying drawings.

The tire PCI method according to the present invention is characterized in that the vulcanization is completed and the pressure of 5.0 kgf / cm2 is applied to the interior of the tire 10 mounted on the PCI rim 11, which is higher than the normal PCI pressure of 1.5 to 2.5 kgf / To hold the tire (10) on the PCI rim (11) accurately by holding the tire (10) for 10 seconds; And a second step of cooling the tire 10 while keeping the internal pressure of the tire 10 at the normal pressure of the PCI when the first step is completed.

In the first step, the time of arrival of the pressure of 5.0 kgf / cm 2 is preferably 25 seconds or less, more preferably 6 to 14 seconds. By shortening the time of arrival of 5.0 kgf / cm 2 pressure, the time required for the tire to be accurately mounted on the PCI rim is shortened and the uniformity performance is improved.

The tire PCI device of the present invention for applying the tire PCI method described above includes a PCI rim 11 on which a vulcanized tire 10 is mounted; A pressure supplier (12) providing pressure to maintain the tire (10) in an expanded state; A pressure pipe (14) connecting the tire (10) and the pressure supplier (12) to provide a PCI pressure; A proportional control valve (15) capable of controlling the pressure of the PCI to a high pressure and a low pressure and installed at one side of the pressure pipe (14); A pressure regulator (13) installed between the proportional control valve (15) and the tire (10) so as to apply a high pressure instantaneously to the tire (10) by increasing the PCI pressure; And a computer 16 for exchanging control signals with the AD converter of the proportional control valve 15 and controlling the proportional control valve 15 by a pressure control program.

The pressure regulator 13 is provided to shorten the arrival time of the pressure of 5.0 kgf / cm 2 against the internal pressure of the tire 10, and shortens the reaching time of 5.0 kgf / cm 2 pressure within 25 seconds to 6 to 14 seconds Thereby accelerating the time point at which the tire 10 is accurately mounted on the PCI rim 11.

In order to rapidly increase the internal pressure of the tire 10, it is preferable to use a 20 mm diameter pipe instead of the existing 15 mm diameter pipe as the pressure pipe 14 for supplying the pressure.

In the tire PCI method and apparatus of the present invention constructed as described above, after the vulcanized tire is mounted on the PCI rim, instantaneous high pressure is applied, and then the PCI process is performed under the normal PCI pressure, .

The green case is vulcanized in the vulcanizer to form the outer shape of the tire, and then the vulcanized tire is mounted on the PCI rim located at the rear end of the vulcanizer. Thereafter, the proportional control valve is adjusted so as to supply the high pressure to the tire, and the internal pressure of the tire is instantaneously raised to 5.0 kgf / cm 2 by supplying pressure through the pressure pipe in the pressure supplier. At this time, it is possible to shorten the arrival time of 5.0 kgf / cm 2 to 6 to 14 seconds by increasing the pressure of the pressure control valve through the pressure regulator, and maintaining the internal pressure of the tire at high pressure for 10 seconds Thereby allowing the tire to be correctly mounted on the PCI rim. Thereafter, the internal pressure of the tire is lowered to 1.5 to 2.5 kgf / cm < 2 >, which is a normal PCI pressure, and the tire is cooled while being maintained for approximately 20 minutes.

As described above, since the normal PCI process is performed in a state that the tire is correctly mounted on the PCI rim, it is possible to prevent the unifority of the finished product tire that may occur due to the erroneous mounting of the tire.

For reference, FIG. 3 shows a case in which the internal pressure change of the tire according to the conventional tire PCI method and the arrival time of 5.0 kgf / cm 2 are limited to 14 seconds (first embodiment) and 6 seconds (second embodiment) And the tire inner pressure change, respectively. Table 1 below shows the results of measuring the uniformity of the finished product tires according to the conventional PCI method and the uniformity of the finished product tires according to the PCI method of the present invention, respectively.

According to the above Table 1, the uniformity performance in the case of the first embodiment in which the reaching time of 5.0 kgf / cm 2 is set to 14 seconds is superior to that of the finished product tires according to the PCI method of the prior art, when the RFV (Radial Force Variation) f, the lateral force variation (LFV) performance is improved by 0.2 kgf, and the R1H (Radial 1st harmonic) performance is improved by 0.6 kgf. In the case of the second embodiment in which the pressure regulator was used to shorten the arrival time of 5.0 kgf / cm 2 to 6 seconds, the RFV performance was improved by 0.3 kgf, the LFV performance was improved by 0.7 kgf, R1H performance does not change. Therefore, the finished product tires according to the first embodiment and the second embodiment all have a superior uniformity performance compared to the finished product tires according to the conventional PCI method.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the true scope of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be interpreted as being included in the scope of the present invention.

10 ... tires
11 ... PCI rim
12 ... pressure feeder
13 ... pressure regulator
14 ... Pressure piping
15 ... proportional control valve
16 ... computers

Claims (6)

The vulcanization is completed and a high pressure is applied to the inside of the tire 10 mounted on the PCI rim 11 in comparison with the normal PCI pressure for a predetermined period of time so that the tire 10 is accurately seated in the PCI rim 11 (1)
And a second step of allowing the tire (10) to cool while maintaining the internal pressure of the tire (10) at the normal PCI pressure when the first step is completed. The method according to claim 1,
In the first step, pressure is applied to maintain the internal pressure of the tire 10 to reach a pressure of 5.0 kgf / cm < 2 > within 25 seconds,
In the second step, the internal pressure of the tire (10) is maintained at a pressure of 1.5 to 2.5 kgf / cm < 2 >. 3. The method of claim 2,
Wherein a reaching time of 5.0 kgf / cm2 in the first step is 6 to 14 seconds. A PCI rim 11 on which a vulcanized tire 10 is mounted;
A pressure supplier (12) providing pressure to maintain the tire (10) in an expanded state;
A pressure pipe (14) connecting the tire (10) and the pressure supplier (12) to provide a PCI pressure;
A proportional control valve (15) capable of controlling the pressure of the PCI to a high pressure and a low pressure and installed at one side of the pressure pipe (14);
And a computer (16) for transmitting / receiving a control signal to / from the AD converter of the proportional control valve (15) and having a pressure control program to control the proportional control valve (15). 5. The method of claim 4,
Wherein a pressure regulator (13) is additionally provided between the proportional control valve (15) and the tire (10) so that a high pressure can be instantaneously applied to the tire (10) by increasing the pressure of the PCI. The method according to claim 4 or 5,
And the diameter of the pressure pipe (14) is 20 mm.

Images