JPS6359093B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for inspecting a tubeless tire rim for air leakage and repairing the air leakage site to prevent air leakage.

The conventional rim air leak testing method uses a submerged method built into the wheel manufacturing line, where the rim is sandwiched between blind plates from both sides and the entire rim is immersed in water. Inspection methods used include applying air pressure or partially sealing the welded part, applying water to the outer diameter of the rim, applying air pressure to the inner diameter, and detecting leaking air bubbles visually or using sound waves. . In addition, if there is an air leak, the rim will be removed from the production line, and if repaired,
It was done by hand in a place off the line.

As a result, inspections involve handling high-pressure compressed air, which requires large-scale equipment, and sensitive inspections using visual inspection pose problems in terms of accuracy and shortening work time.In addition, air leak detection and repair are difficult. This was done separately, which was inefficient, and also caused problems in automating wheel manufacturing and saving labor.

In order to solve the above problems, the present invention replaces the submersion test with a vacuum test to improve the accuracy and time of the test, and at the same time, uses the suction power of the vacuum to test the sealant coating material in the same process as the test. To provide an air leakage inspection method and device capable of repairing leakage parts by infiltrating defective parts and repairing them, improving efficiency and automating wheel manufacturing.

To achieve this objective, the air leak prevention test of the present invention involves sealing off the inside diameter of a tubeless tire rim from the atmosphere and evacuating it to a vacuum state, and then blowing a detection gas such as helium or freon from the outside of the rim. It consists of a method and device that checks whether there is any gas leaking into the inner diameter of the rim, sprays or applies sealant to the rim, and uses vacuum to seep the sealant into defects such as cracks. be done. However, the confirmation of the presence or absence of the detection gas leaking to the inner diameter side of the rim and the spraying or coating of the sealing material may be carried out either first or in a later step.

Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the apparatus used to practice the invention. In the figure, reference numeral 1 denotes a tire rim, which is set on a tire rim mounting table 3 of a feeder 2. The feeder 2 is movable along a guide 4 in the Y direction in the figure. The mounting table 3 can move up and down with respect to the feeder 2, and by these movements, the tire rim 1 set on the mounting table 3 at the tire rim supply position B can be moved to the inspection position A.

A pair of blind plates 5 and 6 are disposed on both sides of the tire rim 1 at the inspection position A in the X direction in the figure. In the illustrated example, at least one of the blind plates 5 and 6 is movable in the X direction along guides 7 and 8, and is driven by cylinders 9 and 10. It is carried out with When the blind plates 5 and 6 are moved toward each other and the tire rim 1 is held between the blind plates 5 and 6,
The inside of the tire rim 1 is shielded from the atmosphere.

As shown in FIG. 2, annular seal rings 11 and 12 made of rubber or the like are provided at the portions of the blind plates 5 and 6 that face the flange 1a of the tire rim 1. When the rim flange 1a is pressed against the rim flange 1a, the seal rings 11 and 12 are brought into pressure contact with the rim flange 1a, thereby creating a complete seal.

The space surrounded by the blind plates 5 and 6 and the tire rim 1 is isolated from the atmosphere and then evacuated, and there is a pipe 1 for removing air from the space.
3 opens on the inner diameter side of at least one of the seal rings 11 and 12 of the blind plates 5 and 6. The piping 1
3 has a flexible pipe 14 or a slide pipe, etc. in the middle, so that movement of the blind plate 5 or 6 can be absorbed.

The pipe 13 is connected to a vacuum pump and a leak detector for a detection gas such as helium. FIG. 3 shows the system of this detection piping. The degree of vacuum is measured with the vacuum gauge 15, the roughing pump 16a is used to make it almost vacuum, and then the main pulling pump 16 is turned on.
The roughing pump 16a and the main pumping pump 16b are arranged in parallel so that they do not create resistance to each other. This circuit includes a leak detector 18 via a test valve 17.
is provided. In the circuit, 19 is an isolation valve, 20 is a roughing valve, 21 is a bypass valve, 22 is a vacuum breaker valve, and 23 is a leak valve.

On the other hand, a detection gas spraying nozzle 24 is disposed on the outer peripheral side of the tire rim 1, and is adapted to spray a detection gas such as helium toward the tire rim 1. The spray nozzle 24 is disposed at a position facing the weld when the tire rim 1 is set on the mounting table 3 with the weld facing up and brought to the inspection position A, and is placed in a position facing the weld. It moves up and down.

A seal coating material spray nozzle 27 is provided on the rod 26 of the register 25, and is adapted to move up and down together with the detection gas spray nozzle 24. A seal coating material spray nozzle 27 is connected to a seal coating material tank 29 by a flexible hose 28, and sprays the seal coating material toward the outer periphery of the rim when the electromagnetic valve 30 is opened. Note that the seal coating material spray nozzle 27 may be replaced by a seal coating material application means.

When the blind plates 5 and 6 sandwich the tire rim 1 and create a vacuum inside the tire rim 1, the blind plates 5 and 6 press the tire rim 1 from both sides due to the pressure difference between the atmosphere and the vacuum. However, since this load is quite large, measures have been taken to prevent the rim flange 1a of the tire rim 1 from being deformed. That is, as shown in FIG. 2, at least one of the blind plates 5 and 6, in the illustrated example, the blind plate 5,
A convex tube 31 extending toward the opposing blind plate is provided, and the convex tube 31 is formed to have a diameter slightly smaller than the inner diameter of the tire rim 1, so that the blind plates 5 and 6 press the tire rim 1. When doing so, it enters into the tire rim 1 and the tip of the convex tube 31 comes into contact with the mating blind plate 6. With this, the convex tube 3
When one tip comes into contact, the load due to pressure is received by the convex cylinder 31, and no further load is applied to the tire rim 1 to deform the tire rim 1.

Reduction of the load due to this pressure can also be achieved as shown in FIG. That is, on the blind plates 5 and 6,
Providing convex tubes 32 and 33 that penetrate the blind plates 5 and 6,
A sealing material 3 is provided between the blind plates 5 and 6 and the convex tubes 32 and 33.
4 and 35 are interposed so that they can freely slide against each other. By doing this, when the inside of the tire rim 1 is evacuated, the blind plates 5 and 6 have a convex tube 3.
2,33 Pressure load is applied only to the outside of the outer diameter,
The clamping pressure load applied to the tire rim 1 can be reduced by the cross-sectional area of the convex tubes 32 and 33 x the load for atmospheric pressure.

In the embodiment shown in FIG. 4, a spring or cylinder is further used to apply a force to pull the slidable convex tubes 32 and 33 in the X direction and in the opposite direction to the opposing blind plate with a force weaker than the convex tube area x atmospheric pressure. A tensioning means consisting of 36, 37 is provided. By doing this, when the inside of the tire rim 1 is evacuated, the blind plates 5, 6 are pressed against the tire rim 1 by the pressure of the vacuum, but when the vacuum is broken, the blind plates 5, 6 are immediately removed. 6 will be separated from the tire rim 1.

Next, the operation of the present invention implemented using the apparatus having the above configuration will be explained.

First, the tire rim 1 is set on the mounting table 3 of the feeder 2 with the welded part facing upward. Next, the feeder 2 is moved in the Y direction to bring the tire rim 1 to the inspection position A. Next, cylinders 9 and 1
0 is activated to move the blind plates 5 and 6 in a direction toward each other, thereby sandwiching the tire rim 1 between the blind plates 5 and 6, and shielding the inside of the tire rim 1 from the outside air. In this case, the inside of the tire rim 1 is completely shut off by the action of the seal rings 11 and 12 provided on the blind plates 5 and 6.

Next, the inside of the tire rim 1 is evacuated. Initially, the roughing pump 16a is operated, and after the pressure is brought to near vacuum in a short time, the main pump 16b is activated.
to create a high vacuum. When the inside of the wheel 11 is evacuated, the load due to the pressure difference between the atmospheric pressure and the vacuum increases, and the blind plates 5 and 6 try to press the tire rim 1 with a strong force, but as shown in FIG. In the embodiment shown in FIG. 4, the pressure load is reduced by the contact between the convex tubes 31, and in the embodiment shown in FIG. It will never occur.

Next, the nozzle 24 for spraying a detection gas such as helium is lowered near the tire rim 1, and spraying of the detection gas, such as helium gas, is started. The area around tire rim 1 is filled with helium gas, so
If there is a defect in the tire rim 1, helium gas is sucked into the tire rim 1 from there.

The sucked helium gas reaches the leak detector 18 through the pipe 13 and is detected with high accuracy. FIG. 5 is a graph showing the relationship between tire pressure and leakage amount. The line P in the figure is the air leakage guarantee reference line, and for passenger cars, the required tire pressure of 1.4 kg/cm ² must be guaranteed for 6 months from one periodic inspection to the next periodic inspection, so the initial filling pressure is 1.8 ~1.9
Assuming Kg/cm ² , the leakage amount must be less than 6.3×10 ^-4 cc/sec. However, in conventional visual inspection, if the leakage rate is 1 bubble/1sec, the equivalent leakage amount is 1.
×10 ^-2 cc/sec (line Q), the tire pressure decreases in a short period of time, and even at the current submergence test level of 1 bubble/3 sec, the equivalent leakage amount is 8 × 10 ^-4 cc/sec.
(line R), which still does not satisfy the guarantee standard. However, in the case of a leak test using helium gas etc. according to the present invention, 3×10 ^-4 cc/sec
(line S) leakage detection is easily performed. This is because the molecular size of the detection gas such as helium is extremely small compared to that of air, so it can easily pass through minute cracks even under a vacuum pressure difference.

When helium is detected and it is confirmed that there is a leak, the solenoid valve 30 is opened and a sealing coating material is sprayed toward the outer circumference of the tire rim 1. In this case, since the inner diameter side of the tire rim 1 is in a vacuum state, the sealing material is drawn into the defect such as a crack and enters the defect, sealing the inside of the defect. Then, use the leak detector again to confirm that the leak has stopped. As a result, repair of leakage sites can be accomplished at the same time during the inspection process.

In addition, in the above explanation, the sealing material is sprayed to repair the leaking area only if there is a leak after conducting a leak inspection, but the order of the steps is not limited to this. Immediately after evacuating the inside of the tire rim 1, spray a sealant on the welded parts of the tire rim 1 and other places where defects may occur, and then spray helium gas to check for leaks. You may do so.

When using the tubeless tire rim air leak prevention inspection device of the present invention, the following various effects can be obtained.

First, we conduct an air leak test using a vacuum.
This vacuum is also used to suck in the sealant coating material to repair rim defects, improving work efficiency in wheel manufacturing, promoting manufacturing automation, and reducing the number of defective products. .

First, since the inspection does not require a conventional water immersion test, the inspection can be facilitated, and since there is no need to provide a water tank or the like, the device can be made smaller and simpler.

In addition, since there is no need to supply high-pressure air to one side of the wheel as is the case with submersion tests, there is no need for large-scale pressure-resistant structures, making it possible to downsize and simplify the equipment as well as making it easier to handle. Be safe.

Furthermore, instead of the conventional sensitive inspection of visualizing blisters, we use mechanical detection, and high-precision detection equipment such as helium leak detectors can be used, greatly increasing the reliability and accuracy of detection. It can be greatly improved.

Furthermore, measurements can be performed in a short time, and together with mechanical detection, it can contribute to the automation of inspections.

In addition, by providing a convex tube on the blind plate or passing the convex tube through, the clamping pressure load from the blind plate on the wheel can be reduced, and problems such as deformation of the wheel rim flange can be eliminated during the inspection process. At the same time, the volume of the vacuum chamber is reduced, and the cycle time for achieving the required vacuum pressure can be shortened.

[Brief explanation of drawings]

FIG. 1 is an overall perspective view of the device according to the present invention, and FIG.
The figure is a front view of the device shown in FIG. 1, FIG. 3 is a vacuum system piping system diagram in the device shown in FIG. 1, FIG. 4 is a partial sectional view of the rim support part in another embodiment of the present invention, and FIG. is a characteristic diagram related to air leakage. 1... Tire rim, 5, 6... Blind plate, 11,
12... Seal ring, 13... Piping, 18...
Leak detector, 24...Detection gas spray nozzle, 27...Seal coating material spray nozzle, 31,
32, 33... convex tube, 36, 37... cylinder.

Claims (1)

[Claims] 1. When a pair of blind plates are provided on both sides of a tubeless tire rim set on an inspection table, at least one of which is movable in the axial direction with respect to the rim, and the rim is held between the blind plates. A sealed space surrounded by the rim and a blind plate is connected to a vacuum pump and a leak detection gas detection device through a pipe whose one end opens into the space, and a leak detection gas spray nozzle is installed on the outer periphery of the rim. A convex tube with a diameter slightly smaller than the inner diameter of the rim is placed in the center of the blind plate, and the tip of the convex tube contacts the opposing blind plate when the blind plate is closed, or slides through the hole and seal in the blind plate. A tubeless tire, characterized in that the tubeless tire is provided in either one of two modes, and is further provided with either a sealing material spraying nozzle or a sealing coating material application means on the outer peripheral side of the rim. Air leak prevention inspection device for rims.