Air tightness detection clamp

Abstract

The utility model relates to an air tightness detection clamp which is characterized in that a lower clamp comprises a groove body defining an annular cavity, the periphery of the groove body is provided with a convex wall extending upwards, the top end of the convex wall is provided with a caulking groove, and the caulking groove is arranged in the lower clamp to define a position facing the inner side and corresponding to a first radial slot; the sealing piece can be detachably inserted into the caulking groove and comprises a first sealing section extending in the up-down axial direction and a second sealing section extending in the inside-outside radial direction; a first gap is formed between the peripheral wall, below the first radial slot, of the to-be-detected object and the convex wall of the groove body, and the first gap and the to-be-detected cavity jointly form an independent closed space through the bottom of the peripheral wall of the to-be-detected object. According to the air tightness detection clamp, only one sealing piece is needed, sealing connection of the whole object to be detected can be achieved, the head and the tail of the object to be detected do not need to be sealed together, and only the shallowest position of the radial slot needs to be sealed.

Description

Technical Field

[0001] The utility model relates to the detection field, in particular to an airtightness detection fixture. Background Art

[0002] When the product needs to be tested for air tightness, the fixture is required to clamp the product to ensure that the product does not move or deform during the air tightness test. At the same time, the fixture has a seal to fill the gap between the clamping surface and the product to ensure the sealing when the clamping surface contacts the product to prevent gas leakage or external gas from entering. The seal is usually made of corrosion-resistant, high-temperature-resistant or high-pressure-resistant materials, such as rubber or silicone.

[0003] If the sealing area is relatively regular, a dedicated sealing detection device is often designed according to the sealing area of ​​the test piece. Figure 1 The product shown is prone to other sealing problems. First, the outer peripheral wall 1' of the product has multiple radial slots 2', and the depths of each radial slot 2' are different. The common sealing method is: the matching seals need to be placed in each radial slot 2' one by one, and then the sealing assembly is used to pressurize each seal so that each seal expands and deforms in the radial direction to achieve the corresponding sealing effect. However, this method not only requires the use of multiple seals, but also makes it difficult to ensure that each seal can be effectively deformed to achieve the sealing effect; secondly, the bottom wall of the product has multiple recesses 3' that are concave upward, and the circumferential width of each recess 3' is different. If the common method of sealing the bottom wall and each radial slot 2' is adopted, so that the cavity to be detected in the product forms an independent closed space, it is necessary to set multiple seals with specific adaptability size and structure to cooperate with the sealing. The scope of use of the sealing tool is relatively narrow, and the selection, assembly and processing of the sealing components are also more complicated. For this reason, it is necessary to further improve the existing sealing method. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide an airtightness testing fixture which can stably perform airtightness testing on the product to be tested in view of the above-mentioned existing technical status, and is particularly suitable for the product to be tested with radial slots of different depths.

[0005] The technical solution adopted by the utility model to solve the above technical problems is: the airtightness detection fixture comprises:

[0006] The lower fixture is used to carry the object to be inspected, the object to be inspected includes a cavity to be inspected facing the lower fixture, the object to be inspected includes an outer peripheral wall and a top wall covering the upper open end of the outer peripheral wall, the outer peripheral wall is formed with a plurality of radial slots, in the direction from top to bottom, the radial slot located at the top and the shallowest is called the first radial slot, and a first interval D1 is left between the bottom of the outer peripheral wall of the object to be inspected and the lower fixture;

[0007] An upper clamp for clamping an object to be inspected; and

[0008] An air intake mechanism, provided on the upper fixture and / or the lower fixture, for supplying air to the cavity of the object to be inspected;

[0009] Features:

[0010] The lower fixture comprises a groove body enclosing an annular cavity, the periphery of the groove body has a convex wall extending upward, the top of the convex wall is provided with an embedding groove, and the embedding groove is provided in the lower fixture to define a position facing inwardly corresponding to the first radial slot;

[0011] A sealing member is detachably inserted into the embedding groove, and includes a first sealing section extending in an up-and-down axial direction and a second sealing section extending in an inside-and-outside radial direction;

[0012] The upper fixture adopts a separate mechanical end face sealing assembly, including:

[0013] A gland plate, which is annular and adapted to surround the top outer periphery of the object to be inspected and is provided with at least two fasteners;

[0014] The first pressure plate can also be selectively arranged under the pressure cover plate. Compared with the pressure cover plate, it has a radial annular sealing section extending radially inward, and an extrusion space for extruding the seal is formed between the first pressure plate and the seal. When the fastener moves axially to provide axial force, the radial annular sealing section can be used to cause the second sealing section of the seal to deform to seal the first radial slot. A first gap is formed between the outer peripheral wall of the object to be inspected under the first radial slot and the convex wall of the slot body. The first gap forms an independent closed space through the bottom of the outer peripheral wall of the object to be inspected and the cavity to be inspected.

[0015] In order to adjust the height of the upper fixture according to the height of the object to be inspected, at least one second pressing plate is further provided between the cover plate and the first pressing plate, and the axial width of each second pressing plate is the same as the axial width of the first pressing plate. In this way, the height can be adjusted by placing different numbers of second pressing plates.

[0016] Furthermore, the cavity to be inspected of the object to be inspected also includes a second cavity located in the center of the cavity to be inspected, the second cavity is formed by the hole wall of the central hole located in the center of the top wall of the object to be inspected extending downward, and a second interval D2 is left between the lower fixture, the second interval D2> the first interval D1, and correspondingly, a middle sealing mechanism is provided on the hole wall of the central hole, and the middle sealing mechanism can be detachably arranged on the groove body of the lower fixture. In this way, as long as the first radial slot and the second cavity are sealed, the first gap, the first interval and the second interval can jointly form an independent closed space for airtightness detection.

[0017] The middle sealing mechanism has a variety of structures. From the perspective of structural simplicity, preferably, the middle sealing mechanism includes a main body that can be passed through the central hole to the lower clamp, and mounting parts for connecting sealing rings are provided at both ends of the main body. When the sealing rings are squeezed, the main body can seal the central hole.

[0018] In order to make the connection between the middle sealing mechanism and the lower clamp more stable, a fastening screw is further provided in the center of the body, and correspondingly, the lower clamp is provided with a socket for inserting the lower end of the fastening screw, and the upper end of the fastening screw is exposed outside the central hole, so that the staff can provide axial fastening force to the sealing ring. In this way, it is convenient for the staff to disassemble and assemble the middle sealing mechanism.

[0019] In order to make the connection between the sealing ring at the end of the body and the lower clamp more stable, further, the end of the body is provided with a first mounting portion for mounting the sealing ring, and correspondingly, the lower clamp is provided with a groove for sealing with the sealing ring. In this way, the staff can quickly disassemble and assemble the sealing ring through the first mounting portion.

[0020] In order to make the installation of the sealing ring at the head end of the body more secure, further, the head end of the body is provided with an outer step, the outer edge of the outer step constitutes the second installation part for installing the sealing ring, and correspondingly, the body is also provided with a first pressing plate and a second pressing plate located on the outer step, wherein an opening for the fastening screw to pass through is provided between the first pressing plate and the second pressing plate, and when the first pressing plate and the second pressing plate are engaged and pressed, the sealing ring can be sealed and connected to the hole wall of the central hole. In this way, the sealing effect of the sealing ring is more stable.

[0021] Compared with the prior art, the advantages of the utility model are: the airtightness detection fixture only needs to use one sealing component to achieve the sealing connection of the entire inspection object. Since a first interval D1 is left between the bottom of the cavity to be detected in the inspection object and the lower fixture, a first gap is cleverly formed between the outer peripheral wall of the inspection object under the first radial slot and the convex wall of the lower fixture. The first gap forms an independent closed space through the bottom of the outer peripheral wall of the inspection object and the cavity to be detected. For this reason, there is no need to consider sealing the head and tail of the inspection object together, and only the shallowest position of the radial slot needs to be sealed. Finally, the use of a separate mechanical end face sealing assembly can be more flexible and easy to maintain when maintaining or replacing the sealing components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of the product to be tested in the background technology of the utility model;

[0023] Figure 2 This is a schematic diagram of the structure of the airtightness detection fixture in the embodiment of the utility model;

[0024] Figure 3 A cross-sectional view of an airtightness detection fixture in an embodiment of the utility model;

[0025] Figure 4 for Figure 3 The enlarged schematic diagram of point A in the middle;

[0026] Figure 5 for Figure 3 A magnified schematic diagram of point B in the middle. DETAILED DESCRIPTION

[0027] The present invention will be described in further detail below in conjunction with the accompanying drawings.

[0028] like Figure 2-5 The figure shows a preferred embodiment of the utility model. An airtightness detection fixture of the present embodiment comprises a lower fixture 1, an upper fixture 2, a middle sealing mechanism 3 and an air intake mechanism.

[0029] The lower fixture 1 is used to carry the object to be inspected 4. The object to be inspected 4 includes an outer peripheral wall 41 and a top wall 42 covering the upper open end of the outer peripheral wall 41, and a first gap D1 is left between the bottom of the outer peripheral wall 41 and the lower fixture 1. The outer peripheral wall 41 is formed with a plurality of radial slots, and the one located at the top and having the shallowest radial slot in the direction from top to bottom is called the first radial slot 4b.

[0030] The cavity 4a of the object to be inspected 4 faces the lower fixture 1, and the cavity 4a also includes a second cavity 4d located in the center of the cavity 4a to be inspected. The second cavity 4d is formed by extending downward from the hole wall of the central hole located in the center of the top wall 42 of the object to be inspected 4, and a second interval D2 is left between the lower fixture 1, and the relationship between the first interval D1 and the second interval D2 is: second interval D2>first interval D1.

[0031] In this embodiment, the lower fixture 1 includes a groove body 11 and a sealing member 14 that encloses an annular cavity. The periphery of the groove body 11 has a convex wall 12 extending upward, and a top end of the convex wall 12 is provided with an embedding groove 13, which is provided in the lower fixture 1 to define a position facing inwardly corresponding to the first radial narrow groove 4b; the sealing member 14 includes a first sealing segment 141 extending in the up-and-down axial direction and a second sealing segment 142 extending in the inner and outer radial directions, and can be detachably inserted into the embedding groove 13.

[0032] like Figure 4 As shown, the upper fixture 2 uses a separate mechanical end face sealing assembly to compress the object 4 to be inspected, specifically including a pressure cover plate 21, a fastener 22, a first pressure plate 23 and a second pressure plate 24. The pressure cover plate 21 is annular and is adapted to surround the top outer periphery of the object 4 to be inspected, and is equipped with a plurality of fasteners 22; the first pressure plate 23 can also be selectively arranged under the pressure cover plate 21. Compared with the pressure cover plate 21, it has a radial annular sealing section 231 extending radially inward, and an extrusion space for extruding the seal 14 is formed between the seal 14. When the fastener 22 moves axially to provide an axial force, the radial annular sealing section 231 can be used to cause the second sealing section 142 of the seal 14 to deform, so as to seal the first radial slot 4b; a second pressure plate 24 is also arranged between the pressure cover plate 21 and the first pressure plate 23, and the axial width of each second pressure plate 24 is the same as the axial width of the first pressure plate 23. Of course, the number of the second pressing plates 24 can be set accordingly according to the height of the object 4 to be inspected.

[0033] In addition, an air intake mechanism (not shown in the figure) is also provided on the upper fixture 2 and / or the lower fixture 1 for supplying air to the cavity 4a of the object 4 to be inspected.

[0034] The middle sealing mechanism 3 is arranged on the hole wall of the central hole located in the center of the top wall 42 of the object to be inspected 4, and can be detachably arranged on the groove body 11 of the lower fixture 1. The middle sealing mechanism 3 includes a body 31, a first sealing ring 32a arranged at the end of the body 31, a second sealing ring 32b arranged at the head end of the body 31, a fastening screw 33, an outer step 34, a first pressing plate 35 and a second pressing plate 36. Among them, the body 31 can be inserted through the central hole to the lower fixture 1, and the center of the body 31 is penetrated with a fastening screw 33. Correspondingly, the lower fixture 1 is provided with a socket 1a for inserting the lower end of the fastening screw 33, and the upper end of the fastening screw 33 is exposed outside the central hole, so that the staff can provide axial fastening force to the first sealing ring 32a and the second sealing ring 32b. When the first sealing ring 32a and the second sealing ring 32b are squeezed, the body 31 can seal the central hole.

[0035] In order to make the installation of the first sealing ring 32a and the second sealing ring 32b more secure and the sealing effect more stable, the end of the body 31 is provided with a first installation portion for installing the first sealing ring 32a, and correspondingly, the lower clamp 1 is provided with a groove 1b for sealing therewith; Figure 5 As shown, an outer step 34 is provided at the head end of the main body 31, and the outer edge of the outer step 34 constitutes a second mounting portion for mounting the second sealing ring 32b. Correspondingly, a first pressing plate 35 and a second pressing plate 36 located above the outer step 34 are also provided on the main body 31, wherein an opening for the fastening screw 33 to pass through is opened between the first pressing plate 35 and the second pressing plate 36, and when the first pressing plate 35 and the second pressing plate 36 are engaged and pressed, the second sealing ring 32b can be sealed and connected to the hole wall of the central hole.

[0036] In this embodiment, a first gap 4c is formed between the outer peripheral wall 41 of the object to be inspected 4 below the first radial slot 4b and the convex wall 12 of the slot body 11. The first gap 4c forms an independent enclosed space through the bottom of the outer peripheral wall 41 of the object to be inspected 4 and the cavity 4a to be inspected.

[0037] The method of using the airtightness detection fixture is as follows: the object 4 to be inspected is positioned on the lower fixture 1 through the main body 31 of the middle sealing mechanism 3, and the sealing member 14 is located at a position corresponding to the first radial slot 4b, and then the first pressing plate 23, the second pressing plate 24 and the pressure cover plate 21 are placed on the sealing member 14 in sequence, and the pressure cover plate 21 is fixed by the fastener 22 and squeezes the first pressing plate 23 and the sealing member 14. The fastener 22 needs to be tightened diagonally when fixed to prevent unevenness when tightened on one side, so that the radial annular sealing segment 231 can cause the second pressure plate 24 of the sealing member 14 to be flat. The sealing section 142 is deformed to seal the first radial slot 4b; the middle sealing mechanism 3 installs the first sealing ring 32a through the first mounting portion, and installs the second sealing ring 32b through the second mounting portion, and then provides axial fastening force to the first sealing ring 32a and the second sealing ring 32b through the fastening screw 33, and the first sealing ring 32a and the second sealing ring 32b are squeezed to seal the central hole; in this way, the first gap 4c forms an independent closed space through the bottom of the outer peripheral wall 41 of the object to be inspected 4 and the cavity 4a to be inspected, which can be inflated to find the leak.

Claims

1. An airtightness detection fixture, comprising: The lower fixture (1) is used to carry an object (4) to be inspected, the object (4) to be inspected includes a cavity (4a) to be inspected facing the lower fixture (1), the object (4) to be inspected includes an outer peripheral wall (41) and a top wall (42) covering the upper open end of the outer peripheral wall (41), the outer peripheral wall (41) is formed with a plurality of radial slots, and the radial slot located at the top and the shallowest in the direction from top to bottom is called the first radial slot (4b), and a first interval D1 is left between the bottom of the outer peripheral wall (41) of the object (4) to be inspected and the lower fixture (1); An upper clamp (2) for pressing an object to be inspected (4); and An air intake mechanism, arranged on the upper fixture (2) and / or the lower fixture (1), and used for supplying air to the cavity (4a) of the object to be inspected (4); Features: The lower fixture (1) comprises a groove body (11) which forms an annular cavity, the periphery of the groove body (11) has a convex wall (12) extending upward, the top of the convex wall (12) is provided with an embedding groove (13), and the embedding groove (13) is provided in the lower fixture (1) to define a position facing inwardly corresponding to the first radial narrow groove (4b); A sealing member (14) is detachably inserted into the embedding groove (13), and comprises a first sealing section (141) extending in an up-and-down axial direction and a second sealing section (142) extending in an inside-and-outside radial direction; The upper fixture (2) adopts a separate mechanical end face sealing assembly, comprising: A pressure cover plate (21) is annular and is adapted to surround the top outer periphery of the object to be inspected (4) and is provided with at least two fasteners (22); The first pressure plate (23) can also be selectively arranged under the pressure cover plate (21). Compared with the pressure cover plate (21), it has a radial annular sealing section (231) extending radially inward, and an extrusion space for extruding the seal (14) is formed between the first pressure plate (23) and the seal (14). When the fastener (22) moves axially to provide an axial force, the radial annular sealing section (231) can be used to cause the second sealing section (142) of the seal (14) to deform so as to seal the first radial slot (4b). A first gap (4c) is formed between the outer peripheral wall (41) of the object to be inspected (4) under the first radial slot (4b) and the convex wall (12) of the groove body (11). The first gap (4c) forms an independent closed space through the bottom of the outer peripheral wall (41) of the object to be inspected (4) and the cavity (4a) to be inspected.

2. The airtightness detection fixture according to claim 1, characterized in that: At least one second pressing plate (24) is also arranged between the pressure cover plate (21) and the first pressing plate (23), and the axial width of each second pressing plate (24) is the same as the axial width of the first pressing plate (23).

3. The airtightness detection fixture according to claim 1 or 2, characterized in that: The cavity (4a) to be inspected of the object to be inspected (4) further includes a second cavity (4d) located in the center of the cavity (4a) to be inspected, and the second cavity (4d) is formed by extending downward from the hole wall of the central hole located in the center of the top wall (42) of the object to be inspected (4), and a second interval D2 is left between the cavity (4a) and the lower fixture (1), and the second interval D2>the first interval D1. Correspondingly, a middle sealing mechanism (3) is provided on the hole wall of the central hole, and the middle sealing mechanism (3) is detachably arranged on the groove body (11) of the lower fixture (1).

4. The airtightness detection fixture according to claim 3, characterized in that: The middle sealing mechanism (3) comprises a main body (31) which can be passed through the central hole to the lower clamp (1), and mounting portions for connecting sealing rings are provided at both ends of the main body (31). When the sealing rings are squeezed, the main body (31) can seal the central hole.

5. The airtightness detection fixture according to claim 4, characterized in that: A fastening screw (33) is provided in the center of the body (31), and correspondingly, the lower clamp (1) is provided with a socket (1a) for inserting the lower end of the fastening screw (33), and the upper end of the fastening screw (33) is exposed outside the central hole, so that the staff can provide axial fastening force to the sealing ring.

6. The airtightness detection fixture according to claim 5, characterized in that: The end of the body (31) is provided with a first mounting portion for mounting a first sealing ring (32a), and correspondingly, the lower clamp (1) is provided with a groove (1b) for sealing in cooperation therewith.

7. The airtightness detection fixture according to claim 6, characterized in that: The head end of the body (31) is provided with an outer step (34), and the outer edge of the outer step (34) constitutes a second mounting portion for mounting the second sealing ring (32b). Correspondingly, the body (31) is also provided with a first pressing plate (35) and a second pressing plate (36) located above the outer step (34), wherein an opening for the fastening screw (33) to pass through is provided between the first pressing plate (35) and the second pressing plate (36), and when the first pressing plate (35) and the second pressing plate (36) are engaged and pressed, the second sealing ring (32b) can be sealed and connected to the hole wall of the central hole.

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