JPH01167629A - Jig for leak inspection - Google Patents

Abstract

PURPOSE:To perform accurate and speedy leak inspection by providing a jig main body around a body to be inspected, applying high-pressure gas from the opening of the body to be inspected, collecting leak gas by a leak gas recovery part formed on the internal wall surface of the jig main body and discharging the leak gas from the jig main body. CONSTITUTION:Frame members 5A and 5B of the jig main body 5 are arranged around a gasoline tank 1 and their flange parts 8 are clamped mutually with clampers 9. A high-pressure gas supply hose 15 is connected to high-pressure air supply port 10 to supply the high-pressure gas to the gasoline tank 1 through an injection port 3. The leak gas leaks in thin grooves in the internal wall surface of the enclosed chamber 6 of the jig main body 5 and is discharged from a leak gas discharge path 11 and introduced to a leak detector device through a leak gas discharge pipe 16, thereby detecting the occurrence of the leak.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a leak testing jig that enables leak testing by supplying high pressure gas to a hollow container.

<Prior art> Conventionally, as a leak inspection method for hollow containers such as automobile gasoline tanks, gas is supplied under pressure into the hollow container to detect leaks from pinballs or welding defects that occur on the walls of the hollow container. There are known methods of detecting leakage using various leak detector devices such as a flow rate needle for supply gas, a pressure gauge, a bubble detector, etc., or by immersing a container in a water tank and visually observing leakage bubbles.

<Problems to be solved by the invention> However, with such conventional leak testing methods,
In the case of a hollow container with a thin plate thickness, such as the above-mentioned gasoline tank of an automobile, high pressure gas cannot be supplied, and an accurate and quick leak test cannot be performed. This is achieved by supplying high-pressure gas into a hollow container with a thin plate.
This is because the hollow container may expand and deform, and the expansion may cause peeling of the welded portion of the container.

In addition, in conventional leak testing methods, the hollow container is immersed in a water tank or the like for testing, so it is necessary to dry the hollow container after the test, which has the disadvantage of requiring large-scale equipment and time. .

In view of the above-mentioned conventional circumstances, the present invention makes it possible to supply high-pressure gas into a hollow container to perform an accurate and quick leak test, and also allows the hollow container to be immersed in a water tank or the like. An object of the present invention is to provide a leak inspection jig for a hollow container, which can eliminate the need for a drying process after inspection by performing a dry type leak inspection.

(Means for Solving the Problems) Therefore, the present invention consists of two frame members that can be combined, and when a hollow object to be inspected is accommodated, an inner part having substantially the same shape as the outer shape of the object to be inspected is provided. A jig body provided to form a sealed chamber with a wall surface, and a pressurizer formed through the frame at a proper location of the jig body and capable of being airtightly connected to an opening of the object to be inspected. a gas supply path; a leak gas recovery section formed directly on the inner wall surface of the jig main body and/or laminated on the inner wall surface; one end communicating with the leak gas recovery section;
The other end is a leak gas discharge port formed by penetrating the frame so as to open outward from the jig main body, and the leak gas discharge port is characterized in that the leak gas discharge port is formed to open outward from the jig main body, and enables leak inspection by supplying high pressure gas. Use as an inspection jig.

(Function) In such a configuration, the hollow container of the object to be inspected that requires leak testing is sealed inside the main body of a hard jig made of metal, etc., and high-pressure gas is supplied to the hollow container from the high-pressure gas supply port. If there is such a problem, gas will leak from the scratches, etc., and this leaked gas will be collected in a gas recovery section consisting of a narrow groove formed on the inner wall of the sealed chamber of the jig main body or stretched in a layer on the inner wall. The leak gas is guided to the leak gas outlet through a gas recovery part such as a hard porous material.Therefore, the leak gas discharged from the leak gas outlet or its pressure change can be detected.In this case, The gas can be collected and discharged while holding the hollow container directly on the inner wall surface of the sealed chamber or by the hard member of the leak gas collection section.
Even when high-pressure gas is supplied into the hollow container, there is no risk of expansion deformation of the hollow container or peeling of the welded joint, and accurate and rapid leakage testing can be performed. Further, it is not necessary to test the hollow container by immersing it in a water tank or the like, and a step of drying the hollow container after the test is no longer necessary, so that it is possible to reduce the number of equipment and shorten the test time.

(Example> Next, one embodiment of the present invention will be described based on the drawings.

In Figures 1 and 2, 1 is a thin gasoline tank which is the object to be inspected for leakage, and 2 parts IA
, IBs are connected to each other by welding the flange portions 2 of the peripheral edges to form a hollow container.

The outer shape of the gasoline tank 1 is such that an uneven portion is formed on the surface.

3 is a gasoline inlet formed in the upper part of the gasoline tank 1, and 4 is an outboard formed in the lower wall portion and communicating with the engine.

5 is a sealed chamber 6 having approximately the same external shape as the gasoline tank 1;
It is a hard jig main body made of metal or the like and consisting of two frame members 5A and 5B that are combined so as to fit the gasoline tank 1 into the sealed chamber 6.

The two frame members 5A and 5B each have a gasoline tank 1.
The frame members 5A and 5B are provided correspondingly to the members IA and IB, respectively, and the joint surfaces of the frame members 5A and 5B are provided in correspondence with the members IA and IB that constitute the frame members 5A and 5B, respectively.
It is formed to match the bonding surface of B. Frame members 5A, 5
A seal member 7 such as an O-ring is interposed on the joint surface of B, and the flanges 8 are integrally assembled by fastening each other with fasteners 9 such as bolts and nuts.

The jig body 5 has a high-pressure gas supply port 10 connected to an inlet 3 formed in the gasoline tank 1, and a Lieli gas discharge port 11 that opens on a part of the inner surface of the jig body 5.
and is provided.

A leak gas recovery section is formed on the inner wall surface of the sealed chamber 6 of the jig main body 5 having the above structure, while holding the gasoline tank 1 and guiding the leak gas to the leak gas outlet 11.

In this embodiment, the leak gas recovery section is a strip groove 12 formed in a mesh lattice shape so as to leave a rectangular wall surface 13 on the inner wall surface of the sealed chamber 6 of the jig main body 5. This strip groove 12 functions as a passage for recovering leak gas, and the rectangular wall surface 13 faces the outer surface of the gasoline tank 1 to keep the gasoline tank 1 in substantially close contact with the inside of the sealed chamber 6 of the jig body 5. It has the function of holding.

The inner end of the leak gas outlet 11 is opened and communicated with the position where the narrow groove 12 is formed.

Next, a method for performing a leak test on the gasoline tank 1 using the leak test jig having the above configuration will be described.

First, the frame member 5 of the jig body 5 is placed around the gasoline tank 1.
A and 5B are arranged respectively, and their flange parts 8 are connected with bolts.
The gas tank 1 is sealed in the jig main body 5 in an air-tight manner by being assembled integrally by fastening with a fastener 9 such as a nut. In this case, a sealing member 14 is inserted into the hole 5a on the inner surface of the frame member 5B into which the outboard 4 of the gasoline tank 1 is fitted, and the opening outer end surface of the outboard 4 is brought into contact with this sealing member 14. The outboard 4
Seal it tightly. Of course, the outboard 4 may be closed in advance with a plug or the like.

Next, a high pressure gas supply hose 15 led from a high pressure gas supply device (not shown) is connected to the high pressure gas supply port 10, while a flow rate cape ↑ and a pressure gauge are connected to the leak gas discharge port 11 to detect gas leakage from the container. , a drain pipe 16 connected to any leak detector device, such as a bubble detector.

In this case, an airtight seal member 17 is provided between the connection end surface of the high-pressure gas supply hose 15 and the open end surface of the injection hole 3 of the gasoline tank 1.
At the same time, an airtight seal member 18 is also interposed between the outer peripheral surface of the high pressure gas supply hose 15 and the inner peripheral surface of the high pressure gas supply port 10. Further, a seal airtight member 19 is also interposed between the outer peripheral surface of the discharge pipe 16 and the inner peripheral surface of the leak gas discharge port 11.

After the gasoline tank 1 is hermetically housed in the jig main body 5 in this way, high pressure gas (for example l
2,000 kg/cd) is supplied into the gasoline tank 1 via the high-pressure gas supply hose 15 and the inlet 3. If there is a scratch or the like on the gasoline tank 1, gas will leak from the scratch or the like, but this leaked gas will leak into one of the slots 12 on the inner wall of the sealed chamber 6 of the jig body 5 and be collected. be done. Therefore, if this amount of leakage is large, the narrow groove 1
The internal pressure of the sealed chamber 6 increases even if it is a small amount. The leak gas discharged from the leak gas discharge port 11 is introduced into the leak detector device via the leak gas discharge pipe 16, or the occurrence of a leak can be detected as an increase in the internal pressure of the sealed chamber 6.

According to the leak inspection jig having such a configuration, the function of the formed thin grooves 12 and the rectangular wall surface 13 allows leakage gas to flow from the gasoline tank 1 while allowing the gas tank l to be It can be held by the jig main body 5 along the shape. Therefore, even if high-pressure gas is supplied into the gasoline tank 1, the gasoline tank 1
There is no possibility of expansion deformation or peeling of welded parts.
Accurate and quick leak tests can be performed. In addition, there is no need to immerse the gasoline tank 1 in a water tank or the like for inspection.
The process of drying the gasoline tank 1 after the inspection is not necessary, and the equipment and inspection time can be reduced.

In addition, in this example, as a leak gas recovery section,
Although the narrow grooves 12 formed in a lattice pattern on the inner wall surface of the sealed chamber 6 are used, other examples include porous ceramic, porous resin, porous casting, porous aluminum, lattice wire mesh, etc. A hard breathable lining material may be formed in layers on the inner wall surface of the sealed chamber 6.

Like the narrow grooves 12, the lining material in this case also functions as a leak gas passage, and also faces the outer surface of the gasoline tank 1 to prevent the gasoline tank 1 from expanding and changing within the sealed chamber 6 of the jig body 5. It has the function of holding it in place.

Further, in this embodiment, the gasoline tank 1 is used as an example of the object to be inspected, but it goes without saying that the present invention can be applied to leak inspection of various other hollow containers.

<Effects of the Invention> As explained above, the leak testing jig of the present invention can hold a hollow container without deforming it while allowing leak gas to flow in a closed chamber. Even when the hollow container is supplied inside, there is no risk of expansion deformation of the hollow container or peeling of the welded portion of the container, and an accurate and quick leak test can be performed. Further, it is not necessary to test the hollow container by immersing it in a water tank or the like, and a step of drying the hollow container after the test is no longer necessary, so that it is possible to reduce the number of equipment and shorten the test time.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a longitudinal sectional view showing an embodiment of the leak testing jig according to the present invention, and FIG. 2 is a plan view showing the inner surface of one frame member of the jig. . 1...Gasoline tank 3...Inlet 5...Jig body 5A, 5B...Divided body 6...Hollow part 10.・High pressure gas supply port 11 ・Leak gas discharge port 12 ・Small groove 13 ・Protrusion Patent applicant Japan Automation Co., Ltd. Agent
Patent Attorney Thousand 1) Minoru 0 N

Claims (3)

[Claims] (1) A cage made of two or more frame members that can be combined and provided so that when a hollow test object is accommodated, a sealed chamber is formed that has an inner wall surface that has approximately the same shape as the external shape of the test object. a pressurized gas supply path that is formed through the frame at a proper location of the jig body and can be airtightly connected to the opening of the object to be inspected; a leak gas recovery section formed and/or laminated on the inner wall surface, one end communicating with the leak gas recovery section;
The other end is a leak gas discharge port formed by penetrating the frame so as to open outward from the jig main body, and the leak gas discharge port is characterized in that the leak gas discharge port is formed to open outward from the jig main body, and enables leak inspection by supplying high pressure gas. Inspection jig. (2) The leak testing jig according to claim 1, wherein the leak gas recovery section is a mesh-like groove formed directly on the inner wall surface of the jig main body. (3) The leak testing jig according to claim 1, wherein the leak gas recovery section is a porous hard ventilation material layer stretched over the inner wall surface of the jig main body.