JP7041450B2 - Leak test sealing device - Google Patents

Description

The present invention relates to a leak test sealing device.

For workpieces such as engines that require airtightness, a leak test is conducted to inspect whether there is a leak by supplying a fluid such as air to the internal space of the workpiece and measuring the fluid pressure. (See Patent Document 1 below).

In performing such a leak test, it is necessary to seal all the openings leading to the internal space to be tested. For example, in a leak test of a cooling water flow path in an engine, in order to seal all the openings of the tubular portion (port) for the cooling water inlet and the cooling water outlet provided in the engine, the opening end face of the tubular portion is sealed. The sealing member was brought into contact with the (tip surface) to prevent air leakage from the open end surface.

Japanese Unexamined Patent Publication No. 9-159566

However, with the conventional seal structure, the tubular portion cannot be completely sealed, and air leakage may occur. Since such an air leak causes an erroneous determination in the leak test, improvement has been sought.

Therefore, when the cause of such a problem was investigated, it was found that the sealing property between the tubular portion and the sealing member was caused by the surface roughness of the open end surface of the tubular portion. .. That is, since the opening end surface of the tubular portion is formed of a relatively rough surface, it is difficult to obtain sufficient adhesion to the sealing member due to the minute irregularities generated on the opening end surface, and air leaks from a slight gap. It turned out that there was a risk. In addition, the sealing member may be damaged or deteriorated due to burrs or burrs generated on the opening end face during processing of the tubular portion, which is also considered to be a cause of deterioration of the sealing property.

In view of such circumstances, it is an object of the present invention to provide a leak test sealing device capable of obtaining good sealing properties.

In order to solve the above problems, the present invention is a leak test sealing device attached to a tubular portion having a tapered surface whose outer peripheral surface has a tapered surface whose diameter is reduced toward the opening end surface, and has an angle with respect to the tapered surface. A first seal portion that is pressed against the surface and contacts in an annular shape in the circumferential direction, and a second seal portion that is formed to have an inner diameter smaller than that of the first seal portion and is pressed at an angle with respect to the opening end face. Provided is a leak test sealing device, which comprises a sealing member having a sealing member.

As described above, in the leak test sealing device according to the present invention, the sealing member is brought into contact with the tapered surface of the tubular portion to ensure good adhesion of the sealing member to the tubular portion (tapered surface). can do.

According to the present invention, it is possible to ensure good adhesion of the sealing member to the tubular portion, so that the sealing property is improved.

It is sectional drawing of the sealing apparatus which concerns on embodiment of this invention. It is sectional drawing of the tubular part in which the sealing device which concerns on this embodiment is attached. It is sectional drawing which shows the state which moved the outer cylinder by a slide. It is sectional drawing which shows the state in the process of attaching a sealing device to a tubular part. It is sectional drawing which shows the state which the sealing device is attached to the tubular part. It is a cross-sectional view which shows the state in which a seal member was in contact with a tubular part in an enlarged manner. It is sectional drawing which shows the sealing member in an enlarged manner. It is sectional drawing of an example in which a through hole is not provided in a valve body. It is sectional drawing for demonstrating the operation of the sealing apparatus which concerns on this embodiment. It is sectional drawing which shows the modification of the seal member. It is sectional drawing which shows the further modification of the seal member.

Hereinafter, embodiments of the leak test sealing device according to the present invention will be described.

FIG. 1 is a cross-sectional view of a leak test sealing device according to the present embodiment.

As shown in FIG. 1, the seal device 1 for a leak test according to the present embodiment has a cylindrical outer cylinder 2, a cylindrical inner cylinder 3 inserted in the outer cylinder 2, and an inner cylinder 3. The valve body 4 housed in the valve body 4, the valve seat 5 that receives the valve body 4, and the first spring as an urging member that urges the outer cylinder 2 toward the tip end side (arrow A direction in the figure) of the inner cylinder 3. 6 and a second spring 7 as a urging member for urging the valve body 4 toward the tip end side of the inner cylinder 3 (in the direction of arrow C in the figure), and a plurality of lock balls 8 as lock members are mainly configured. It is supposed to be.

The outer cylinder 2 and the inner cylinder 3 are assembled so as to be relatively movable in the axial direction, and normally, the outer cylinder 2 is moved to the tip end side of the inner cylinder 3 by the urging force of the first spring 6. It is being held. The first spring 6 is mounted in a compressed state between the stepped portions 2a and 3a provided on the inner peripheral surface of the outer cylinder 2 and the outer peripheral surface of the inner cylinder 3, respectively. Further, a plurality of recesses 2b through which the lock ball 8 can enter are provided on the inner peripheral surface of the outer cylinder 2. The lock ball 8 is provided so as to be movable outward and inward in the radial direction of the inner cylinder 3. As shown by the two-dot chain line in FIG. 1, the outer cylinder 2 is moved toward the rear end portion side of the inner cylinder 3 (in the direction of arrow B in the figure) against the urging force of the first spring 6, and the outer cylinder 2 When the recess 2b is arranged at a position corresponding to the lock ball 8, the lock ball 8 enters the recess 2b and becomes movable outward in the radial direction.

The valve body 4 is accommodated in the inner cylinder 3 so as to be movable in the axial direction. A concave seat surface 4a, 5a for receiving the end portion of the second spring 7 is formed on the rear end surface of the valve body 4 and the front end surface of the valve seat 5, respectively, and a second seat surface 4a, 5a is formed between these seat surfaces 4a, 5a. The spring 7 is arranged in a compressed state. The valve body 4 is constantly urged toward the tip end portion of the inner cylinder 3 by the second spring 7, but the stepped portions 4b provided on the outer peripheral surface of the valve body 4 and the inner peripheral surface of the inner cylinder 3 respectively. By engaging the 3b with each other and functioning as a stopper portion, the valve body 4 is prevented from falling off from the inner cylinder 3. Further, the valve body 4 is provided with a through hole 4c formed so as to penetrate from the front end surface to the rear end surface.

As shown in FIG. 1, a tubular sealing member 9 made of an elastic body such as rubber is provided at the tip of the valve body 4. The inner peripheral surface of the seal member 9 is formed in a stepped shape, and is located on the rear end side of the valve body 4 with respect to the first seal portion 10 having a large inner diameter and the first seal portion 10, and the first seal portion. It has a second seal portion 11 having an inner diameter smaller than 10. Further, an O-ring (rubber ring) 12 of another sealing member is mounted on the outer peripheral surface of the valve body 4, and the space between the valve body 4 and the inner cylinder 3 is sealed by the O-ring 12.

The valve seat 5 is fitted and fixed to the rear end portion of the inner cylinder 3. An O-ring (rubber ring) 13 as a sealing member is mounted on the outer peripheral surface of the valve seat 5, and the space between the valve seat 5 and the inner cylinder 3 is sealed by the O-ring 13.

Next, a method of using the sealing device according to the present embodiment will be described by taking as an example a case where the sealing device is used for a leak test of a cooling water flow path of an automobile engine. However, the leak test sealing device according to the present invention is not limited to the leak test of the cooling water flow path of the engine, but is not limited to the leak test of the oil flow path of the engine, the leak test of the air flow path for air supply and exhaust, and further other than the engine. It can also be applied to leak tests performed on workpieces.

FIG. 2 is a cross-sectional view of a tubular portion to which the sealing device according to the present embodiment is mounted.

The tubular portion 20 is a portion to which a piping member such as a hose that circulates cooling water between the engine and the radiator is attached, and as shown in FIG. 2, communicates with the fluid path 31 of the cooling water in the engine 30. It is provided so as to project outward from the engine 30 so as to do so. Further, a plurality of tubular portions 20 are provided for a cooling water inlet and a cooling water outlet, and an opening end surface 20a (tip surface) is provided on the outer peripheral surface of each tubular portion 20 so that a piping member can be easily attached. ), A tapered surface 20b is formed.

In conducting the leak test, it is necessary to attach the sealing device according to the present embodiment to the tubular portion to seal the opening of the tubular portion. It should be noted that the sealing device is attached to all the other tubular portions except one among the plurality of tubular portions. An air supply device (not shown), which is a test fluid supply device, is connected to the remaining one tubular portion.

To attach the sealing device to the tubular portion, first, as shown in FIG. 3, the outer cylinder 2 of the sealing device 1 is placed on the rear end side of the inner cylinder 3 against the urging force of the first spring 6. Slide to move. Next, as shown in FIG. 4, the sealing device 1 is attached to the tubular portion 20 so that the tubular portion 20 is inserted into the inner cylinder 3 while the outer cylinder 2 is held in a slid-moved state. Plug it in. At this time, since the lock ball 8 is in a state where it can enter the recess 2b of the outer cylinder 2, the lock ball 8 is pushed outward in the radial direction along the tapered surface 20b of the tubular portion 20. It is possible to get over the tapered surface 20b.

Then, as shown in FIG. 5, the holding of the outer cylinder 2 is released in a state where the open end surface 20a and the tapered surface 20b of the tubular portion 20 are pressed against the seal member 9 of the valve body 4. As a result, the outer cylinder 2 is pushed toward the tip end side of the inner cylinder 3 by the urging force of the first spring 6, and the lock ball 8 has the inner peripheral surface (the portion without the recess 2b) and the tubular portion 20 of the outer cylinder 2. It will be in a state of being sandwiched between the outer peripheral surface and the outer peripheral surface of the. As a result, the lock ball 8 is pressed against the outer peripheral surface of the tubular portion 20, and the sealing device 1 is fixed to the tubular portion 20. This completes the mounting of the sealing device 1 on the tubular portion 20.

In addition, the sealing device is attached to other tubular parts by the same procedure. Then, air is supplied from the air supply device into the fluid path of the engine, and a leak test is performed to check for air leaks. After the leak test is completed, in order to remove the sealing device from the tubular portion, the removal operation may be performed in the reverse procedure of the above mounting procedure. Specifically, the outer cylinder 2 is slid to the rear end side of the inner cylinder 3 against the urging force of the first spring 6, and the fixing by the lock ball 8 is released. That is, by sliding the outer cylinder 2 toward the rear end portion side of the inner cylinder 3, the lock ball 8 can enter the recess 2b of the outer cylinder 2, so that the lock ball 8 is in the tubular portion 20. The fixed state pressed against the outer peripheral surface is released. Then, while holding the outer cylinder 2 in a slid-moved state, the sealing device 1 is pulled out from the tubular portion 20 and removed.

In a state where the sealing device 1 is attached to the tubular portion 20, as shown in FIG. 6, the sealing member 9 of the valve body 4 is pressed against the open end surface 20a and the tapered surface 20b of the tubular portion 20. As a result, the opening end surface 20a and the tapered surface 20b are sealed at two locations. Specifically, the first seal portion 10 of the seal member 9 is pressed against the tapered surface 20b of the tubular portion 20, and the second seal portion 11 of the seal member 9 is pressed against the open end surface 20a of the tubular portion 20. You can guess.

As described above, in the sealing device 1 according to the present embodiment, the first sealing portion 10 comes into contact with the tapered surface 20b of the tubular portion 20 and the second sealing portion 11 is attached to the tubular portion 20. Can be sealed at two points, the tapered surface 20b and the opening end surface 20a, by contacting the tubular portion 20 with respect to the opening end surface 20a. In particular, since the outer peripheral surface of the tubular portion 20 including the tapered surface 20b is a place where a piping member such as a hose is attached, the processing quality is generally better and the surface roughness is smaller than that of the open end surface 20a. Good adhesion can be obtained between the tapered surface 20b having such a small surface roughness and the first sealing portion 10. In the conventional configuration, since the seal member is brought into contact with only the open end surface of the tubular portion having a relatively large surface roughness, there is a risk of air leaking from the seal portion. By bringing the seal member 9 (first seal portion 10) into contact with the tapered surface 20b having a small surface roughness, good adhesion can be obtained and air leakage from the seal portion can be reliably prevented. Further, since the tapered surface 20b has no burrs or burrs, deterioration of the sealing member 9 (first sealing portion 10) can be suppressed, and good sealing properties can be maintained for a long period of time.

Further, the first seal portion 10 according to the present embodiment is formed in a rectangular cross section having substantially right-angled corner portions E (see FIG. 7), and the first seal portion 10 is pressed against the tapered surface 20b. At that time, the corner portion E is compressed (see FIG. 6). At this time, the corner portion E of the first seal portion 10 is appropriately elastically deformed, so that the first seal portion 10 is in annular contact with the tapered surface 20b in the circumferential direction (entire circumference), resulting in good sealing. Can exert sex.

Further, the outer peripheral surface of the first seal portion 10 is supported by the inner peripheral surface of the valve body 4 so as not to open too much outward in the radial direction when pressed against the tapered surface 20b (see FIG. 6). .. The valve body 4 is made of a highly rigid member such as metal, and by supporting the first seal portion 10 from the outer peripheral side thereof, the adhesion force of the first seal portion 10 to the tapered surface 20b can be obtained. I am assisting.

Further, in the sealing device 1 according to the present embodiment, the second sealing portion 11 is in contact with the open end surface 20a of the tubular portion 20 to be sealed, and the first sealing portion 10 is not excessively elastically deformed. It also plays a role of regulating the insertion position of the tubular portion 20. As a result, excessive elastic deformation of the first sealing portion 10 due to the pushing of the tubular portion 20 can be suppressed, appropriate elastic deformation of the first sealing portion 10 is possible, and good sealing performance can be obtained.

Further, in the sealing device 1 according to the present embodiment, the sealing property is improved by providing the valve body 4 with the through hole 4c (see FIG. 1). On the contrary, when there is no through hole 4c in this respect, as shown in FIG. 8, the valve body 4 receives the air pressure P from the tip surface side thereof, so that the valve body 4 is pushed by the air pressure P and is in a posture. Is unstable, so that the adhesion between the open end surface 20a of the tubular portion 20 and the sealing member 9 is lowered, and there is a possibility that air leaks. On the other hand, when the valve body 4 is provided with the through hole 4c as in the sealing device 1 according to the present embodiment, a part of the air passes through the through hole 4c and the valve is valved as shown in FIG. Since the valve body 4 moves to the rear end surface side of the body 4, the valve body 4 receives the air pressure P from the rear end surface side, and the adhesion of the seal member 9 to the open end surface 20a and the tapered surface 20b of the tubular portion 20 is improved. At the same time, the posture of the valve body 4 becomes stable. Further, by allowing the valve body 4 to receive the air pressure P from the rear end face side in this way, measures are taken to increase the urging force of the second spring 7 in order to stabilize the posture of the valve body 4. Since it is not necessary to take measures, it is possible to avoid deterioration of maintainability due to strengthening the spring force. When the through hole 4c is provided, the air moving toward the rear end surface side of the valve body 4 also enters the gap between the valve body 4 and the inner cylinder 3 and the gap between the valve seat 5 and the inner cylinder 3. Since these are sealed by O-rings 12 and 13, air leakage is prevented.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

For example, as in the example shown in FIG. 10, the first seal portion 10 and the second seal portion 11 are formed of separate seal members, and the first seal portion 10 is a seal having a rectangular cross section having corner portions. Instead of the member, it may be a sealing member having no corners and having a circular cross section or the like. In this case, the first seal portion 10 and the second seal portion 11 can be made of different materials, and a material suitable for each function can be selected. For example, in consideration of the function of each sealing portion, rubber having a hardness of 50 ° can be selected as the material of the first sealing portion 10, and rubber having a hardness of 30 ° to 40 ° can be selected as the material of the second sealing portion 11.

Further, in the above-described embodiment, in order to suppress excessive elastic deformation of the first seal portion 10, a second seal portion 11 is provided to regulate the insertion position of the tubular portion 20, but the seal member If excessive elastic deformation of the first seal portion 10 can be suppressed by changing the material or shape of the first seal portion 10, the second seal portion 11 is omitted and the tubular portion is formed only by the first seal portion 10 as in the example shown in FIG. It may be sealed between the tapered surface 20b of 20 and the tapered surface 20b. As described above, as long as the tapered surface 20b is securely sealed, it is possible to prevent air leakage without providing the second seal portion 11.

Further, the leak test sealing device according to the present invention is not limited to the sealing device for sealing the opening of the tubular portion as described above, but also for the sealing device provided in the fluid supply device for supplying the fluid for the leak test. Applicable. That is, even in the connection portion of the fluid supply device connected to the tubular portion of the work, by providing a seal member (first seal portion) that comes into contact with the tapered surface of the tubular portion, the tapered surface is the same as in the above embodiment. Good adhesion is obtained between the seal member and the seal member, and air leakage from the seal portion can be reliably prevented.

1 Sealing device 2 Outer cylinder 3 Inner cylinder 4 Valve body 5 Valve seat 6 1st spring 7 2nd spring 8 Lock ball 9 Sealing member 10 1st sealing part 11 2nd sealing part 20 Cylindrical part 20a Open end surface 20b Tapered surface

Claims (1)

A leak test sealing device attached to a tubular portion having a tapered surface whose outer peripheral surface is tapered toward the opening end surface.
The first seal portion that is pressed against the tapered surface at an angle and makes annular contact in the circumferential direction and the inner diameter that is smaller than the first seal portion are formed at an angle with respect to the opening end surface. A leak test sealing device comprising a sealing member having a second sealing portion to be held and pressed against.

Images