JPH04223142A - Method for applying stripe pattern onto side wall of tire and its device - Google Patents

Abstract

PURPOSE:To provide the method for applying stripe pattern onto the side wall of the tire and its device by a method in which the necessities of specified rubber compound, the cover of the tire, the groove for limiting the border of the band for decoration and the rotation of a coating device are omitted. CONSTITUTION:A tire is sealed and expanded between a pair of chucks 14, 16. The part of the side wall of the tire to be decorated is kept at flat and horizontal position by the chuck and the expansion pressure. Next, while coating is directly applied onto the tire by the gun 34 which has the tip brought into contact with the side wall of the tire, the type is rotated. The heating elements for curing or partially curing the coating are placed and kept at the same position on the side wall so that the band of the coating is heated with the passing of the tire through under the heating elements.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention is in the field of pneumatic tire manufacturing;
More particularly it belongs to giving decorative features to their side walls. In particular, the present invention relates to a method and apparatus for providing decorative sidewalls to cured tires.

BACKGROUND ART It is well known to provide white or colored bands around the lateral circumference of pneumatic tires. The "white sidewall" tire is generally accepted as the hallmark of a premium tire and is often required to enhance the character and style of the vehicle on which it is used.

There are various known methods for producing "white wall" bands in tires. The basic prior art teaches placing an extruded inlay into the carcass of a tire during manufacture and, after a curing operation, polishing it to reveal a uniform decorative sidewall stripe. Furthermore, spraying,
Attempts to paint or embed such decorative bands are known, but the prior art typically involves (a) wrapping a specially compounded white rubber over the uncured tire carcass during carcass assembly; , (b) put a cover on the cured tire and air spray paint with the paint, or (c) make a groove for that purpose in the side wall of the tire to contain the paint and pour the paint into the groove. or (d) rotating a paint application head around a fixed tire.

Prior to the present invention, (a) the cost and complexity inherent in extruding specially composite rubberized inlays; (b) the time and cost associated with covering and cleaning the cover during spray operations; c) the necessity of having grooves in the side walls to retain the paint therein; (d) the need to rotate the painting device itself around a fixed tire; and (e) the need to install a tire without loss due to overspray. It was most desirable to have decorations on the side walls.

DETAILED DESCRIPTION OF THE INVENTION In view of the foregoing, a first aspect of the present invention is to provide a method and apparatus for striping the sidewall of a tire without the need for special rubber compounds.

Another aspect of the present invention is the provision of a method and apparatus for striping the sidewall of a tire without covering the tire.

Yet another aspect of the present invention is the provision of a method and apparatus for striping the sidewall of a tire without the need for grooves in the tire sidewall to define the borders of the decorative band.

Another aspect of the present invention is the provision of a method and apparatus for striping the sidewall of a tire without the need to rotate the coating equipment.

Yet another aspect of the present invention is the provision of a method and apparatus for striping the sidewall of a tire with substantially reduced losses.

The foregoing and other aspects of the invention, which will become apparent as the detailed description proceeds, are characterized by: a first means for restraining a tire and sealing a cavity within the tire; second means in communication with the tire for inflating the tire by compressing the tire; third means for rotating the tire about the central axis of the tire; and a fixed position relative to the rotating tire. means for applying a paint stripe placed parallel to the tire for holding the paint stripe and applying the paint onto the sidewall of the tire as it rotates past the paint stripe application means; , is achieved by means of a device for applying decorative strips to the sidewalls of tires.

Other aspects of the invention which will now become apparent include: restraining a tire to seal an internal cavity of the tire; inflating said tire to a predetermined pressure; and applying paint onto the sidewall of the tire from a fixed position relative to the tire during said rotation.

With reference now to the best mode diagram for carrying out the invention, and more particularly to FIG.
You will see that it is shown in This system 1
0 is for applying a decorative concentric band on the sidewall of the tire 12, a circular band centered on the axis of the tire. This tire 12 is a hardened tire and is not provided with grooves in the sidewalls for the purpose of delimiting decorative bands as previously required by certain prior art technologies.

The tire 12 is positioned between an upper bead chuck 14 and a lower bead chuck 16 which are matched to constrain the tire bead for sealing therein, thereby enclosing the tire internal cavity. Seal. A piston 18, driven by a pneumatic source or motor 20, is connected to an upper bead chuck 14 that reciprocates to constrain and unconstrain the upper tire bead to obtain the desired seal. An air nozzle 22 extends from the chuck 14 and connects through a hose 24 to an air pressure source 26. Assemblies 22-26 include tires 12
and act to inflate and seal it between chucks 14 and 16. Preferably, the air pressure source 26 also includes a pressure sensor for monitoring the inflation pressure of the tire 12 so that inflation can be terminated at a fixed level.

The piston 28 is connected to the lower bead chuck 1.
6 and therein is brought together and uncoupled with the lower bead of the tire 12 by a pneumatic source or motor 30 to seal and unseal. Typically, the reciprocating motion of chucks 14 and 16 may occur simultaneously and, in any event, chuck 1
4 and 16 may be driven separately from the same pneumatic source. Of course, it will be appreciated that the lower bead chuck 16 may be fixed vertically such that the sealing restraint is achieved and removed by reciprocating movement of the upper bead chuck 14 through the piston 18 and pressure source 20. Probably. In such a structure, the reciprocating piston 28 and pressure source 30 can be eliminated.

The motor 32 is connected to a piston shaft 28 for rotating the shaft about its longitudinal axis, and through the restraint of the chuck 16 on the lower bead of the tire 12 the decorative band is to be applied. The tire 12 is rotated about a vertical axis while keeping the upper tire sidewall portion in a horizontal plane. A paint striping gun and associated tip 34 is connected through a hose 36 to a pressurized source of paint 38. The gun and tip 34 are connected to a retractable piston 40 controlled by a pneumatic or hydraulic motor 42 for extension and retraction.
are connected to each other by. The piston and motor assemblies 40 and 42 operate to extend the striping gun and constrain the tip 34 against the sidewall of the tire 12 to be decorated. next,
Paint is applied by pressure from a source 38 through the tip of the hose 36 and gun 34, and the paint is applied onto the sidewall surface of the tire as the tire rotates. gun 34
When held in a fixed position and the tire 12 is rotated about the axis of its ring, it has a center corresponding to the center of the ring of the tire and a width determined by the width of the gun tip 34. A perfect circular ring of paint is obtained.

A heat source kept parallel to the side wall of the tire, such as a lamp, heating coil, blower, or similar device which, when passed under it, serves to cure or solidify the paint defining the decorative band. It also causes things to exist.

As shown in FIG. 2, the control circuit 50 is
It may serve to regulate and control the operation of the structure of FIG. As shown, comparator 52 has a negative input connected to a voltage divider 54 that determines the limit for the level of inflation of tire 12 that can be obtained for the striping process. The positive input of this comparator 52 is coupled to the air pressure source 26, which includes a pressure sensor for monitoring tire pressure, as described above. When the tire pressure reaches the limit value determined by the pressure divider 54, the comparator 52 emits a positive output signal which passes and initiates the various elements connected to that output. .

As shown, once the tire 12 reaches the desired pressure, inflation is stopped by closing the valve on the air pressure source 26. Simultaneously, a pneumatic or hydraulic motor 42 is actuated to extend the piston 40 and move the striping gun 34 into a position parallel to the sidewall of the tire 12 so that its tip is in contact with the sidewall. I will receive it. At said point of contact restraint determined by a limit switch or other suitable means, the piston 40
stops expanding. Of course, the stroke of the piston itself can be determined for the above purpose.

The output of comparator 52 also activates motor 32, which begins rotation of tire 12. At the same time, the tip of the gun 34 is brought into contact with the tire, and the motor 32 is brought into constant rotation speed.
After a predetermined period of time sufficient for .times. to be reached, timer 56 is started so that gun 34 is started and paint is dispensed from supply 38. This timer 56 recognizes the rotation of the tire and allows the gun 3 to run for a period sufficient for one complete rotation of the tire.
4, thereby placing a complete circular band of paint on the side wall surface. This timer 56 compensates for the response time for starting and stopping gun 34. If the lag times for starting and stopping gun 34 are the same,
This timer simply activates gun 34 for a period of time corresponding to one rotation of tire 12. However, if the lag time is different, correction is made by adjusting the timer 56. Of course, the lag time is preferably determined not only by the mechanism 34 itself, but also by the viscosity and pressure of the paint being applied.

Other structures and techniques for starting and stopping the flow of paint from gun 34 could also be used. For example, timing marks or lugs may be placed on the rotating chuck 14 or 16 to constrain a limit switch to indicate the start and stop of rotation. Similarly, a light source is placed adjacent to the area to be striped so that the light reflected from the tip of the paint strip and sensed by the light detection mechanism serves as a timing signal to control the cessation of paint flow. and a light detection mechanism may be arranged.

The output of comparator 52 also starts timer 58, which determines the curing cycle for operation of heating element 44. Preferably, the timer 58 includes a delay so that the heating element 44 is activated at the appropriate time. In one embodiment of the invention, the activation of heating element 44 is delayed for a sufficient period of time to ensure that the paint solvent has been released after the band has been painted. Typically, this timer 5
The delay of 8 is a function of paint composition and tire rotation parameters. Preferably, this timer 58 holds the heating element 54 there for a period corresponding to several revolutions of the tire 12. This heating element 44 provides curing of the paint, or at least partial or preliminary curing thereof. When the above period ends, timer 5
8 turns off heating element 44, unbinds or turns off motor 32, and activates air pressure sources 20 and 30 to release chucks 14 and 16. Next, the tire 12
Take it out and install another tire so you can start anew.

Several characteristics are observed regarding the preferred operation of the present invention. The striping gun 34 is typically of the spring-loaded tip type that maintains constant contact of the tip against the sidewall of the tire 12 to provide a smooth and even application of the paint. Let them be restrained. A suitable gun for this purpose is the Paasche Airbrush Compan
0.5 width, such as Model SNF manufactured by Chicago, Illinois.
Model A-USBT automatic spring gun with a flat tip measuring 0.015 inches tall. It will, of course, be understood that various types of striping instruments and tips may be used to satisfy the concepts of the present invention. Tire 12 as shown in the figure
It is further shown that the tip preferably restrains the tire 12 while rotating from left to right at an angle of 70° to 85°, preferably 80°. Finally, a striping gun of the type described preferably includes an actuation valve for starting or stopping the painting operation. The part of the tire sidewall that receives the paint strip is preferably manufactured from a clean rubber stock so that the painted strip can remain undamaged. Prior to striping, the sidewall sections are prepared by wiping with a long-fiber ripple cloth, preferably presoaked in 1,1,1-trichloroethane (TCE) or other suitable cleaning solvent. This surface is then coated with 1,3,5-trichloro-s-triazine-2 in 50/50 ethyl acetate/TCE by holding an application brush or other suitable application device against a rotating tire. 4,6
- Prime with a 24% solution of Trion. The application is preferably self-positioned and activated, and subsequent activation of heating element 44 is for about 1 minute to dry the primer.

The paint used for the striping method of the invention is preferably a polyurethane paint with high flexibility and high durability. The polyurethane polymer in this paint is a saturated diisocyanate, such as H12MD.
I (hydrogenated diphenyl diisocyanate) polycaprolactone prepolymer. The prepolymer is cured with a diol or polyol, such as butanediol, trimethylolpropane, propanediol, and the like. In a preferred embodiment of the invention, a catalyst such as a 10% dibutyltin diacetate solution in MEK/xylene is added to the coating. Suitably, the catalyst is added in a range of 1 to 5%, preferably 2 to 4% by weight of the coating components.

What is particularly important regarding the selection of this paint is that
It is its viscosity. Most preferably, the viscosity of the paint is between 40 and 3
It is 70 centipoise. Such a viscosity is necessary so that the paint does not flow or deform after it is deposited from the gun 34 onto the tire surface, but retains the defined confines when extruded from the tip of the gun 34. be.

[0025] To maintain the desired viscosity, it is necessary to add a thinner or diluent to the paint. It has been found that a diluent consisting of a solvent such as n-butyl acetate, ethylbenzene, propylene glycol methyl ether acetate, dipropylene glycol methyl ether, etc. can be added in sufficient quantities to obtain the desired viscosity of 40 to 370 centipoise. Ta. By using a paint with the above viscosity,
It has been found that a low pressure head can be used in the compressed paint source 38 to provide the smooth flow desired to obtain uniformly decorated sidewalls. It has been found that a head pressure of less than 7 psi, preferably on the order of 3-5 psi is sufficient for the above purpose. Obviously, it is important to maintain the pressure at a constant level, which is desired to rotate the tire 12 at a constant speed. Synchronous motors have been found suitable for the above purpose.

The key to successful implementation of this ready-to-use invention is to maintain the side wall to be decorated in a flat, horizontal position. Chucks 14 and 16 must be precisely and evenly aligned, and tire 1
2 must be placed there so that there is no distortion. By properly chucking and inflating the tire, the surface of the sidewall to be decorated can be held flat and level. The above conditions, obtained by maintaining a suitable distance between the beads of the tire and inflating this tire to a certain pressure level, demarcate the boundaries at acute angles and prevent flows that tend to deform the decoration. Or it helps to put paint on the tire to prevent deformation.

It will therefore be appreciated that the objects of the invention are met by the structure shown above. While only the best mode and preferred embodiments of the invention have been shown and described in detail in accordance with the patent regulations, it is understood that the invention is not limited thereto or thereby. Therefore,
For an understanding of the actual scope and meaning of the invention, please refer to the claims.

The features and aspects of the present invention are as follows.

1. a first means for restraining the tire and sealing its internal cavity; a second means coupled to the tire for inflating the tire by pressurizing said cavity; a third means for rotating the tire; and a third means held in a fixed position relative to the rotating tire and passing means for striping paint onto the sidewall of the tire as the tire rotates. Apparatus for applying a decorative band to the sidewall of a tire, comprising: means for striping the paint juxtaposed to the tire;

2. The first means constrains the opposing beads of the tire in a spaced apart relationship such that the sidewalls remain horizontal, and the third means constrains the opposing beads of the tire in a spaced apart relationship such that the sidewalls remain horizontal, and the third means 2. The apparatus of claim 1, comprising rotating said tire.

3. 3. The apparatus of claim 2, wherein said second means comprises inflating said tire to an inflation pressure such that said sidewall receiving said paint is flat and horizontal.

4. 4. The apparatus of claim 3, wherein said paint has a viscosity of 40 to 370 centipoise.

5. 5. The apparatus of claim 4 further comprising a pressurized paint source in communication with said paint striping means having a pressure head of less than 7 psi.

6. 2. The device of claim 1, wherein said paint is a polyurethane paint.

7. 2. The apparatus of claim 1 further comprising means coupled to said tire for sensing pressure within said cavity of said tire.

8. further coupled to said third means and said striping means for starting said striping means at the beginning of rotation of said tire about said axis and for stopping said striping means at the end of said rotation; 8. The apparatus according to claim 7, comprising control means for controlling.

9. said striping means being movably positioned relative to the tire, said control means moving said striping means to said fixed position for applying said paint, and said at the end of said application of said paint said an eighth step comprising removing said striping means from a fixed position;
Apparatus described in section.

10. 10. The apparatus of claim 9 further comprising heating means co-located with the rotating tire and regulated by said control means for heating and curing said paint applied thereto.

11. 11. The apparatus of claim 10, wherein said third means comprises a synchronized motor.

12. constraining the tire to seal the internal cavity of the tire; inflating the tire to a predetermined pressure; rotating the tire about its axis; and during the rotation from a fixed position relative to the tire; A method for applying a decorative band to the sidewall of a tire, comprising applying a paint onto the sidewall of said tire.

13. 13. The method of claim 12, comprising inflating the tire to a pressure such that the portion of the sidewall that receives the paint is flattened.

14. 14. The method of claim 13, further comprising securing said tire with opposing beads and holding said beads in a fixed spaced apart relationship to hold said portion of said side wall flat which receives said paint. Method.

15. 15. The method of claim 14, comprising rotating said tire about a vertical axis and said sidewall being in a horizontal plane.

16. 16. The method of claim 15, wherein the step of applying the paint begins at a time after the start of the step of rotating the tire to ensure that the tire is rotating at a constant speed.

17. 17. The method of claim 16, further comprising heating the paint on the sidewall subsequent to painting, the heating curing the paint.

18. 18. The method of claim 17, comprising continuing said rotation of said tire for a period of time after said painting step.

19. Claim 17, wherein the step of painting comprises moving and restraining the painting device into contact with the sidewall of the tire prior to applying the paint, and removing the painting device following the painting. the method of.

[Brief explanation of the drawing]

In order to fully understand the purpose, technology and structure of the present invention,
The following detailed description and accompanying diagrams are for reference:

[
1 is an illustrative diagram of a system for striping a tire according to the invention; and

FIG. 2 is a diagram of a control circuit for carrying out the method for striping of the present invention using the system of FIG. 1;

Claims (2)

[Claims] 1. A first means for constraining the tire and sealing an internal cavity thereof; a second means coupled to the tire for inflating the tire by pressurizing the cavity; a center of the tire; third means for rotating the tire about an axis; and held in a fixed position relative to the rotating tire and passing means for streaking the paint so that the tire rotates. Apparatus for applying a decorative band to the sidewall of a tire, comprising: means for striping the paint juxtaposed to the tire, sometimes for depositing the paint on the sidewall of the tire. 2. restraining a tire to seal an internal cavity of the tire; inflating the tire to a predetermined pressure; rotating the tire about an axis of the tire; and, during the rotation, against the tire; A method for applying a decorative band to the side wall of a tire, comprising applying paint onto the side wall of said tire from a fixed position.