Breathability test fixture

Abstract

The utility model discloses an air permeability test fixture, including external thread base, internal thread upper cover, columnar cavity, gasket, support pillar, press block, ventilation duct, the external thread base top is covered with the internal thread upper cover in threaded connection, the external thread base top is coaxially slotted and forms the columnar cavity, the two gasket are stacked in the columnar cavity, the support pillar is provided with the pressure block, the pressure block is provided with the pressure block, and the pressure block is provided with the pressure block. An opening is formed in the center of the internal thread upper cover and connected with a top column in an inserted mode, a pressing block which is integrally formed and covers the gasket is arranged at the lower end of the top column, and holes are coaxially formed in the centers of the top column, the gasket and the external thread base to form a ventilation pipeline. By adopting the mode, the air permeability test fixture provided by the utility model aims at the problems of air leakage and pressure relief caused by a single-gasket clamping mode, and the reliability of the test fixture and the accuracy of detection data can be remarkably improved as the diaphragm is fixed by adopting a mode of simultaneously pressing the double gaskets by double-sided threads.

Description

Technical Field

[0001] The utility model relates to the field of film clamps, in particular to an air permeability testing clamp. Background Art

[0002] For tetrafluoroethylene (PTFE) films, the air permeability of PTFE films produced by different formulas and processes varies greatly, and the finished products under the same conditions may also have slight differences. During the production process, the finished products need to be continuously sampled and tested to ensure the stability of product quality.

[0003] The sample clamping device used in the mainstream air permeability tester on the market is divided into four parts, the upper and lower parts, a gasket, and a two-section strong clamp. When in use, place the sample film on the gasket, clamp the gasket with the upper and lower parts, and then fix and seal the upper and lower parts with two sections of strong clamps. This structure is convenient to use, and the replacement and installation of samples are fast. It is widely used in the industry, but this sealing method has general sealing performance. During the test, air leakage and pressure relief may occur at the clamp. At the same time, since the clamp is fixed by tightening the buckle screw, it cannot be guaranteed that the tightness of each fixation is the same. The above situations may lead to inaccurate test results.

[0004] The sealing performance of the existing clamping device is average. During the test, air leakage and pressure relief may occur at the clamp. At the same time, since the clamp is fixed by tightening the buckle screw, it cannot be guaranteed that the tightness of each fixation is the same. At the same time, if the buckle is tightened too hard, it is easy to damage the clamping device. All of the above situations may lead to inaccurate test results. When testing the air permeability of polytetrafluoroethylene film, it is necessary to sample and test at multiple points on the test sample. The area required for sampling with the existing clamping device is about 20cm2, and the effective test area is only 2cm2, which is inefficient and easy to cause material waste. Utility Model Content

[0005] The main technical problem solved by the utility model is to provide an air permeability test fixture. In order to solve the problem of air leakage and pressure relief caused by a single gasket clamp method, the diaphragm is fixed by a double gasket and double-sided threaded compression method, thereby significantly improving the reliability of the test fixture and the accuracy of the test data.

[0006] In order to solve the above technical problems, a technical solution adopted by the utility model is: to provide an air permeability test fixture, including an externally threaded base, an internally threaded upper cover, a columnar cavity, a gasket, a top column, a pressure block, and a ventilation duct, the top of the externally threaded base is covered with an internally threaded upper cover with threads connected thereto, the top of the externally threaded base is coaxially grooved to form a columnar cavity, two gaskets are stacked in the columnar cavity, the central opening of the internally threaded upper cover is inserted with a top column, the lower end of the top column is provided with a pressure block which is integrally formed and covers the gasket, the top column, the gasket, and the externally threaded base have coaxial openings in the center to form a ventilation duct.

[0007] In a preferred embodiment of the present invention, the external thread base is composed of a threaded portion and a base portion, the diameter of the base portion is larger than the diameter of the threaded portion, and a transition step is formed between the threaded portion and the base portion.

[0008] In a preferred embodiment of the present invention, a layer of membrane sample clamping space is formed between the gaskets.

[0009] The beneficial effect of the utility model is that the utility model provides an air permeability test fixture, which can significantly improve the reliability of the test fixture and the accuracy of the test data by fixing the diaphragm by a double-gasket and double-sided threaded compression method to solve the problem of air leakage and pressure relief caused by a single-gasket clamp method. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0011] Figure 1 It is an exploded view of an air permeability test fixture of the utility model;

[0012] Figure 2 This is a split structure diagram of an air permeability test fixture of the utility model;

[0013] Figure 3 The utility model is a combined structural diagram of an air permeability testing fixture. DETAILED DESCRIPTION

[0014] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] like Figure 1-3 As shown, the embodiment of the utility model includes:

[0016] A gas permeability test fixture comprises an externally threaded base 1, an internally threaded upper cover 2, a columnar cavity 3, a gasket 4, a top column 5, a pressing block 6, and a ventilation duct 7. The top of the externally threaded base 1 is covered with an internally threaded upper cover 2 connected with threads. The top of the externally threaded base 1 is coaxially grooved to form a columnar cavity 3. Two gaskets 4 are stacked in the columnar cavity 3. The central opening of the internally threaded upper cover 2 is inserted with a top column 5. The lower end of the top column 5 is provided with a pressing block 6 which is integrally formed and covers the gasket 4. The top column 5, the gasket 4, and the central opening of the externally threaded base 1 are coaxial to form a ventilation duct 7.

[0017] The external thread base 1 is composed of a threaded portion and a base portion, the diameter of the base portion is larger than the diameter of the threaded portion, and a transition step is formed between the threaded portion and the base portion.

[0018] Furthermore, a layer of membrane sample clamping space is formed between the gaskets 4. The top column 5 is screwed to press the pressing block 6 with the gasket 4, thereby compressing the membrane sample clamping space.

[0019] On the one hand, this product improves the sealing method of the clamping device mentioned in the background technology from clamp fixing to upper and lower thread fixing, which simplifies the number of parts of the clamping device, makes the operation more convenient and has better sealing. On the other hand, the number of gaskets 4 is increased to two pieces, changing the original single-piece sealing to double-sided sealing, further improving the sealing. The above two improvements can effectively avoid the problem of inaccurate test results caused by the original structure. The simpler structure ensures the stability of the clamping device for long-term use. Since there is no need for clamp fixing, it is changed to upper and lower parts of thread fixing. At the same time, the upper half is divided into a thread fixing part (the internal thread upper cover 2) and a part connecting the ventilation pipe 7 (the top column 5 and the pressure block 6). Since the structure that can replace the ventilation pipe 7 (including the top column 5, the gasket 4 and the external thread base 1) separately can be used, the effective area of ​​the test can be selected as 1cm² or 2cm² according to the needs, and the required sample area is also greatly reduced. When the effective area required for the test is 1cm², the area required for sampling is only 5cm², which can effectively reduce the cost of use.

[0020] In the second embodiment, the spiral fixing structure of the upper part of the clamp and the connection part with the ventilation pipe 7 are made into an integral structure. That is, the top column 5, the pressing block 6, and the internal thread upper cover 2 are set as an integral structure, and the gasket 4 is compressed by tightening the internal thread upper cover 2.

[0021] In summary, the utility model provides an air permeability test fixture, which can solve the problem of air leakage and pressure relief caused by the single gasket 4 clamp method. Since the diaphragm is fixed by double gaskets 4 with double-sided threaded compression, the reliability of the test fixture and the accuracy of the test data can be significantly improved.

[0022] The above description is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A gas permeability test fixture, characterized in that: It includes an externally threaded base, an internally threaded upper cover, a columnar cavity, a gasket, a top column, a pressure block, and a ventilation duct. The top of the externally threaded base is covered with an internally threaded upper cover with threads connected thereto. The top of the externally threaded base is coaxially grooved to form a columnar cavity. Two gaskets are stacked in the columnar cavity. The central opening of the internally threaded upper cover is plugged with a top column. The lower end of the top column is provided with a pressure block that is integrally formed and covers the gasket. The top column, gasket, and externally threaded base have coaxial openings in the center to form a ventilation duct.

2. The air permeability test fixture according to claim 1, characterized in that: The external thread base is composed of a threaded portion and a base portion. The diameter of the base portion is greater than the diameter of the threaded portion. A transition step is formed between the threaded portion and the base portion.

3. The air permeability test fixture according to claim 1, characterized in that: A layer of membrane sample clamping space is formed between the gaskets.

Images