CN111693227A

CN111693227A - Air tightness testing device

Info

Publication number: CN111693227A
Application number: CN201910190576.1A
Authority: CN
Inventors: 李明; 张平; 刘小龙; 孙聚川; 耿见宇; 羌小龙; 何玉喜; 吉晶
Original assignee: 711th Research Institute of CSIC
Current assignee: Shanghai Marine Diesel Engine Research Institute; 711th Research Institute of CSIC
Priority date: 2019-03-13
Filing date: 2019-03-13
Publication date: 2020-09-22

Abstract

The invention provides an air tightness testing device which comprises a support, an upper sealing tool and a lower sealing tool, wherein the support is arranged on an operating platform; the upper sealing tool is arranged on the support and can move vertically relative to the support, the upper sealing tool is provided with a cavity and a sealing cover for sealing the top port of the test piece, and the sealing cover is arranged in the cavity; the lower sealing tool is arranged on the operating platform and can move transversely relative to the support, the lower sealing tool is provided with a receiving part, the receiving part corresponds to the cavity, when the lower sealing tool moves to the position below the upper sealing tool and is covered by the upper sealing tool, a closed testing space is formed between the cavity and the testing piece, and the air tightness testing device senses the pressure change of compressed gas input into the testing space to judge the air tightness of the testing piece. The air tightness testing device can realize air tightness testing of the testing piece with the special-shaped structure, is simple in testing process, and can improve the automation level of the device, so that the labor cost is saved.

Description

Air tightness testing device

Technical Field

The invention relates to the technical field of air tightness testing, in particular to an air tightness testing device.

Background

The air tightness test is an important inspection process for ensuring the product quality, and is widely applied to the technical fields of automobile manufacturing, bathroom hardware, household appliances, medical instruments, refrigeration equipment, valve pipelines and the like. Existing methods for testing the hermeticity of a product or workpiece are usually performed by an operator with the aid of a tool. The general test method is that the mouth of the test piece is sealed and then filled with compressed air, then the test piece is immersed in water, and whether bubbles are generated or not is observed by naked eyes to judge the tightness of the test piece. The defects that the product is easy to fatigue after long-time visual observation, and micro bubbles generated in the test process of the product with a complex structure are easy to attach to the inner wall of the product and are difficult to discharge, which can cause the sealing performance of the product to be misjudged.

Therefore, there is a need for a gas tightness testing device to at least partially solve the problems of the prior art.

Disclosure of Invention

In this summary, concepts in a simplified form are introduced that are further described in the detailed description. This summary of the invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In order to solve the above-mentioned problems at least in part, according to an aspect of the present invention, there is provided a airtightness testing apparatus for testing a test piece having a body and a mounting member, a bottom portion of the mounting member being mounted to the body, a top portion of the mounting member having a top port, the airtightness testing apparatus comprising:

the bracket is arranged on the operating table;

the upper sealing tool is arranged on the support and can move vertically relative to the support, the upper sealing tool is provided with a cavity with a downward opening and a sealing cover for sealing the top port, and the sealing cover is arranged in the cavity; and

a lower sealing tool which is arranged on the operating platform and can move along the transverse direction relative to the bracket, the lower sealing tool is provided with a receiving part for receiving the test piece, the receiving part corresponds to the cavity,

when the lower sealing tool moves to the lower part of the upper sealing tool and is covered by the upper sealing tool, a closed testing space is formed between the cavity and the testing piece, so that the air tightness testing device senses the change of the pressure of compressed gas input into the testing space to judge the air tightness of the testing piece.

Optionally, the containment caps are spaced apart and have the same or different heights and sizes.

Optionally, the upper surface of the lower sealing tool is a plane, and the lower sealing tool is further provided with an opening forming the receiving portion, so that when the test piece is received in the opening, the peripheral portion of the test piece can be lapped on the upper surface.

Optionally, the lower sealing tool is provided with a positioning pin extending upwards and protruding out of the upper surface, the positioning pin is arranged around the opening to position the test piece, and the upper sealing tool is provided with a receiving hole corresponding to the positioning pin to receive the positioning pin.

Optionally, the method further comprises:

the first pneumatic element is arranged on the bracket, a push rod of the first pneumatic element is connected to the upper sealing tool through a guide plate connected with the bracket, and the guide plate is movable relative to the bracket; and

and the second pneumatic element is arranged on the operating platform and connected with the lower sealing tool.

Optionally, the lower surface of the upper sealing tool is a plane, the cavity is recessed upwards from the lower surface, and the sealing cover does not protrude from the lower surface.

Optionally, the upper sealing tool is provided with a sealing ring at the peripheral edge of the cavity, so as to be connected at the peripheral edge of the test piece in a sealing manner.

Optionally, the test device further comprises a gas tightness tester connected to the upper sealing tool through a pipeline, wherein the pipeline extends into the cavity to input compressed gas into the test space.

Optionally, a control unit is provided in the airtightness tester, the control unit being configured to compare a measured pressure of the test piece with a predetermined pressure determined in accordance with a pressure of a standard piece measured by the airtightness testing apparatus to determine whether the test piece leaks.

Optionally, the control unit is further configured to store predetermined pressures corresponding to different standard pieces, and to associate corresponding predetermined pressures according to the test piece.

The airtight testing device can seal the top port of the testing piece by means of the upper sealing tool, and can form a closed testing space between the testing piece placed in the lower sealing tool and the upper sealing tool, so that the airtight testing device can sense the pressure change of compressed gas input into the testing space, and the airtightness of the testing piece is judged, and particularly the airtightness between the bottom of the mounting part and the body is judged. The air tightness testing device can realize air tightness testing of the testing piece with the special-shaped structure, is simple in testing process, and can improve the automation level of the device, so that the labor cost is saved.

Drawings

The following drawings of the invention are included to provide a further understanding of the invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles and apparatus of the invention. In the drawings, there is shown in the drawings,

fig. 1 is a schematic perspective view of a airtightness testing apparatus according to a preferred embodiment of the present invention;

FIG. 2 is a schematic rear view of the air tightness testing device shown in FIG. 1;

FIG. 3 is a schematic perspective view of the test strip of FIG. 2;

FIG. 4 is a schematic perspective view of the upper sealing tool shown in FIG. 1, wherein the upper sealing tool is in an inverted state; and

fig. 5 is a block diagram of a production line of test pieces including the airtightness testing apparatus shown in fig. 1.

Description of the reference numerals

100: the airtightness testing apparatus 110: support frame

120: lower sealing tool 130: upper sealing tool

131: the plugging cover 131 a: first plugging cover

131 b: second plugging cover 132: die cavity

133: sealing ring 134: second peripheral part

135: receiving hole 136: second positioning pin

141: first pneumatic element 142: second pneumatic element

143: pressing element 144: base seat

145: pressing portion 151: guide plate

152: fixing plate 160: track

170: airtight tester 180: start button

200: the test piece 210: body

211: groove 212: a first peripheral part

213: flanging 220: mounting component

220 a: first mounting member 220 b: second mounting member

221: the top port 300: operation table

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention.

In the following description, for purposes of explanation, specific details are set forth in order to provide a thorough understanding of the present invention. It is apparent that the practice of the invention is not limited to the specific details set forth herein as are known to those of skill in the art. The following detailed description of the preferred embodiments of the present invention, however, the present invention may have other embodiments in addition to the detailed description, and should not be construed as being limited to the embodiments set forth herein.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention, as the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. When the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The terms "upper", "lower", "front", "rear", "left", "right" and the like as used herein are for purposes of illustration only and are not limiting.

Ordinal words such as "first" and "second" are referred to herein merely as labels, and do not have any other meaning, such as a particular order, etc. Also, for example, the term "first mounting component" does not itself imply the presence of "second mounting component", and the term "second mounting component" does not itself imply the presence of "first mounting component".

In the following, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings, which illustrate representative embodiments of the invention and do not limit the invention.

The invention provides an air tightness testing device which can be used for testing the air tightness of a testing piece with a special-shaped structure.

As shown in fig. 1 and 2, the airtightness testing apparatus 100 is disposed on an operation table 300. The structure of the operation table 300 is not limited. The airtightness testing apparatus 100 includes a support 110 and a lower seal fixture 120 provided on an operation table 300, and an upper seal fixture 130 provided on the support 110. The upper sealing tool 130 can be vertically movable relative to the bracket 110 to cover the lower sealing tool 120. The lower sealing tool 120 is capable of placing the test piece 200 and is movable in the lateral direction with respect to the rack 110 together with the test piece 200. When the lower sealing tool 120 can move to the lower side of the upper sealing tool 130 and be covered by the upper sealing tool 130, a sealed test space can be formed between the upper sealing tool 130 (specifically, the cavity 132 below) and the test piece 200.

Specifically, the lower sealing tool 120 is movable in the transverse direction between a first initial position and a first testing position. The first initial position is located outside the support 110 so as to place the test piece 200 to the lower sealing tool 120. The first testing position is located at the support 110 and below the upper sealing tool 130. The upper sealing tool 130 can vertically move between a second initial position and a second testing position, the second initial position is located above the second testing position, and the upper sealing tool 130 can cover the lower sealing tool 120 at the second testing position.

In the present embodiment, the test piece 200 is a special-shaped piece having a special-shaped structure. Fig. 3 exemplarily shows an embodiment of the test piece 200, and the test piece 200 includes a body 210 and a mounting part 220. The bottom of the mounting part 220 is mounted to the body 210, for example, fixed to the body 210 by screws. The airtightness testing apparatus 100 can detect the airtightness between the bottom of the mounting member 220 and the body 210. The inside of the mounting member 220 is open from the bottom up, and the top of the mounting member 220 has a top port 221. The top port 221 is open. Alternatively, the body 210 may be configured in a substantially rectangular parallelepiped shape. The top of the body 210 may be provided with a groove 211 having an upward opening, the groove 211 being depressed downward from an upper surface of the first peripheral portion 212 of the body 210. The mounting member 220 is mounted in the recess 211 and protrudes from the primary peripheral portion 212. The primary peripheral portion 212 is annular and has a horizontally outwardly extending flange 213. The upper surface F1 of the flange 213 is shown as being planar to facilitate sealing.

Accordingly, as shown in fig. 4, the upper sealing tool 130 is provided with a sealing cover 131 for sealing the top port 221. The position of the blocking cover 131 corresponds to the position of the mounting member 220. The blocking cover 131 may be adapted to the shape of the mounting member 220 and may also be substantially rectangular. In this embodiment, when the test piece 200 is tested for airtightness, the airtightness testing apparatus 100 can test whether the mounting part 220 is hermetically connected to the body 210.

The blocking cover 131 may be detachably mounted to the upper sealing tool 130 by means of, for example, screws. The number of the blocking covers 131 may be the same as the number of the test pieces 200, for example, the test piece 200 may include at least two mounting members 220 arranged at intervals, the upper sealing tool 130 may be provided with at least two blocking covers 131 arranged at intervals, and the blocking covers 131 correspond to the mounting members 220 one to one. Three blocking covers 131 are exemplarily shown in the figure, for example a first blocking cover 131a for closing a first mounting member 220a, a second blocking cover 131b for closing a second mounting member 220b, etc. The height of the blocking cover 131 is adapted to the height of the mounting member 220. The heights of the containment caps 131 may be the same or different. For example, the first mounting member 220a in the illustrated embodiment has a height greater than that of the second mounting member 220b, and the first blocking cover 131a has a height less than that of the second blocking cover 131 b. The size of the blocking cover 131 may be adapted to the size of the mounting member 220. The blocking cap 131 may be the same size or different sizes. For example, the first mounting member 220a has a size larger than that of the second mounting member 220b, and the first blocking cover 131a has a size larger than that of the second blocking cover 131 b.

Further, since the mounting member 220 protrudes from the first peripheral portion 212 of the body 210 in the illustrated embodiment, the upper sealing tool 130 is provided with a cavity 132 that is opened downward to partially receive the mounting member 220. The cavity 132 is recessed upward from the lower surface F2 of the upper sealing tool 130. The blocking cap 131 is disposed in the cavity 132 and does not protrude from the lower surface F2. Of course, in an embodiment not shown, the mounting member 220 may not protrude from the first peripheral portion 212 of the body 210, and the blocking cover 131 may not protrude from the lower surface F2 of the upper sealing tool 130.

Accordingly, the lower sealing tool 120 is provided with a receiving portion for receiving the test piece 200. The receiving portion can correspond to the cavity 132 described above. Specifically, when the upper sealing tool 130 is closed to the lower sealing tool 120, the receiving portion corresponds to the cavity 132. The test piece 200 is placed in the receiving portion so that it is restrained. In the illustrated embodiment, the undercover 120 is provided with an opening (not shown) forming a receiving portion. The shape of the opening is adapted to the shape of the top of the test piece 200. The test piece 200 may be placed from above the lower sealing tool 120 and received in the opening. The first peripheral portion 212 of the test piece 200 is overlapped to the upper surface of the lower sealing tool 120 by the flange 213, and the middle-lower portion of the test piece 200 is suspended.

The upper surface of the lower sealing tool 120 may be a plane, and the lower surface F2 of the upper sealing tool 130 may be a plane, so that the two can be better closed. Referring back to fig. 4, the upper sealing tool 130 may also be provided with a sealing ring 133. The sealing ring 133 is disposed at the second peripheral portion 134 of the cavity 132 and can correspond to the first peripheral portion 212 of the test piece 200 to sealingly connect at the first peripheral portion 212 of the test piece 200. Specifically, when the upper sealing tool 130 is closed to the lower sealing tool 120, the position of the sealing ring 133 corresponds to the position of the first peripheral portion 212.

Alternatively, the lower sealing tool 120 may be provided with a first positioning pin (not shown) extending upward and protruding from an upper surface thereof, the first positioning pin being disposed around the opening to position the test piece 200. The upper sealing tool 130 is provided with a receiving hole 135 corresponding to the first aligning pin to receive the first aligning pin. Receiving hole 135 is located outside of seal ring 133. The upper sealing tool 130 may be provided with a second positioning pin 136 (fig. 4) extending downward and protruding from the lower surface F2 thereof, and the second positioning pin 136 is diagonally disposed. The lower sealing tool 120 is provided with a positioning hole corresponding to the second positioning pin 136 to receive the second positioning pin 136. Therefore, the upper sealing tool 130 can be positioned to a preset position of the lower sealing tool 120.

Referring back to fig. 1, in the illustrated embodiment, the airtightness testing apparatus 100 further includes a first pneumatic element 141 and a guide plate 151 provided on the support 110. The guide plate 151 is movable relative to the bracket 110, and the first pneumatic member 141 is mounted to the top of the bracket 110 through the fixing plate 152, and its push rod is connected to the upper sealing tool 130 through the guide plate 151. When the push rod pushes the guide plate 151 to move vertically, the sealing tool 130 also moves vertically together. The first pneumatic element 141 may be a cylinder with a piston rod.

The airtightness testing apparatus 100 further includes a second pneumatic element 142 and a rail 160 provided on the operation table 300. The lower sealing tool 120 is disposed on the rail 160 and connected to the second pneumatic element 142. The second pneumatic element 142 is disposed below the lower sealing tool 120 and between the two rails 160. The track 160 is arranged to extend inwardly towards the support 110, and the second pneumatic element 142 is capable of pushing the lower sealing tool 120 to move along the track 160. So that the lower sealing tool 120 is conveyed into the support 110. The second pneumatic element 142 may be a rodless cylinder.

Optionally, the gas tightness testing device 100 may further include a pressing member 143 provided on the operation table 300. The hold-down element 143 includes a base 144 and a hold-down portion 145 (fig. 2) rotatable relative to the base 144. The pressing part 145 is in a rest position (refer to the pressing element 143 on the left side in fig. 2) during the vertical movement of the upper sealing tool 130, and the pressing part 145 does not obstruct the movement of the upper sealing tool. The pressing part 145 rotates from the rest position to a pressing-down position (refer to the pressing-down element 143 on the right side in fig. 2) when the upper sealing tool 130 moves to the second testing position, and at this time, the pressing-down element 143 provides a downward pressing force to the upper sealing tool 130, so that the upper sealing tool 130 better covers the lower sealing tool 120 and better seals with the testing part 200. . The pressing members 143 are symmetrically disposed at both sides of the bracket 110. . .

The gas tightness testing apparatus 100 further includes a gas tightness tester 170 (fig. 1), and the gas tightness tester 170 is connected to the upper sealing tool 130 via a pipe (not shown) extending into the cavity 132 to input a compressed gas into the test space. The air-tightness tester 170 has substantially the same structure as an existing air-tightness tester 170, and for example, a sensor or the like is provided inside. A control unit is provided in the air tightness tester 170, and a start button 180 connected to the control unit is provided on the operation panel 300. The user initiates the operation of the entire device by operating the start button 180. In other words, the control unit starts controlling the operation of the pneumatic elements described above, as well as the air tightness tester 170, in response to the command signal of the start button 180. The start button 180 includes 2, two-handed touch buttons.

The control unit is configured to compare the measured pressure of the test piece 200 with a predetermined pressure determined according to the pressure of the standard piece measured by the airtightness testing apparatus 100 to determine whether the test piece 200 leaks. In the present embodiment, first, the airtightness of a standard material having a structure substantially identical to that of the test material 200 is tested by the airtightness testing apparatus 100, and a predetermined pressure, which is a measurement pressure of the standard material under a certain test condition, is obtained. And then testing the air tightness of the test piece 200 under the same test condition, wherein in the test process, the pressure in the test space at the beginning of the test is the preset pressure, the measured pressure is obtained after the test is finished, and the measured pressure is compared with the preset pressure to judge whether leakage exists. For example, if the measured pressure is less than the predetermined pressure, the leak is determined, whereas the airtightness is determined to be good.

The control unit is also configured to store predetermined pressures corresponding to different standard pieces, and to associate the corresponding predetermined pressures according to the test piece 200. That is, the test pieces 200 of different structures each correspond to a predetermined pressure of a standard piece having substantially the same structure as that of the test piece. Different predetermined pressures and different measured pressures are stored in the control unit, so that the control unit can automatically associate the predetermined pressures after the test piece 200 is identified, and data backup and later product quality control are facilitated.

Alternatively, the design conditions of the airtightness testing apparatus 100 may include:

1) the temperature range of the working environment is 5-45 ℃.

2) The air source is cold-dried compressed air with pressure not less than 0.5MPa and flow not more than 0.5m³Min (operating condition of the single airtightness testing apparatus 100).

3) The environmental humidity is 10-80% RH.

The specific test procedure of the airtightness test apparatus 100 is as follows:

the test piece 200 is placed into the lower sealing tool 120 located at the first initial position, the start button 180 is touched by both hands, and the device starts to operate. The second pneumatic element 142 pushes the lower sealing tool 120 to move to the first testing position, i.e., below the upper sealing tool 130. The first pneumatic element 141 pushes the upper sealing tool 130 to move from the second initial position to the second testing position, and then the pressing element 143 presses the upper sealing tool 130 downwards, at this time, the lower sealing tool 120 is covered by the upper sealing tool 130. Compressed air with certain pressure is input into the testing space, then the inflating air source is automatically turned off, and the test is started after the air flow pressure is stable. At the start of the test, the sensor in the air tightness tester 170 measures a test pressure (i.e., a predetermined pressure), and at the end of the test, the sensor measures a measured pressure, and it is determined whether the bottom of the mounting part 220 leaks or not by the magnitude of the difference between the predetermined pressure and the measured pressure. Specifically, the compressed air leaks from the test space to the inside of the mounting part 220. In performing the product airtightness test, an exemplary embodiment of the test conditions is a test pressure of 40Kpa, an inflation time of 22S, a steady pressure time of 10S, and a test time of 10S. The leakage value is less than 100 Pa. The monitor screen of the air tightness tester 170 may display the status in the leak test, as well as the leak value.

An exemplary embodiment of a production line including the hermetic test apparatus 100 is described below in conjunction with fig. 5. As shown in fig. 5, the manufacturing line includes a wire harness base assembling station ST10, a circuit board assembling station ST20, a wire harness assembling station ST30, a first relay assembling station ST40, a second relay assembling station ST50, an air tightness testing device 100, a testing and assembling station ST60, and an upper case assembling station ST70, which are sequentially arranged in the manufacturing line. A first manual feeding station ST01 and a second manual feeding station ST02 are provided outside the production line, the first manual feeding station ST01 being located beside the wire harness seat assembling station ST10, the second manual feeding station ST02 being located beside the wire harness assembling station ST 30. Wherein, first artifical loading station ST01 includes operations such as the material loading of plastics drain pan, high pressure sampling pencil, circuit board, insurance baffle, installation screw, screw to and bundle ribbon. Second manual work material loading station ST02 includes the material loading of copper bar, main negative relay, sweeps the sign indicating number, and mounting nut sets up operations such as buckle sheath to the copper bar. The test and assembly station ST60 includes insulation testing, voltage withstand testing, and relay marking operations.

In addition, in the production line, the bar code reader is adopted to collect the identification of the product label, the identification can be a two-dimensional code, and the collected information can be product production state information. Then, the data transmission system and the platform management system are used for being in butt joint with an MES (manufacturing execution system), so that the production state information of the product can be monitored and recorded in real time, the selected information is displayed on a monitoring screen, and the prompt is given to an operator.

By arranging the air tightness testing device 100 on the production line, the automation level of the production line can be improved, and the production efficiency can be improved.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Terms such as "part," "member," and the like, when used herein, can refer to either a single part or a combination of parts. Terms such as "mounted," "disposed," and the like, appearing herein may refer to one mounting component being directly attached to another mounting component, or may refer to one mounting component being attached to another mounting component through an intermediary. Features described herein in one embodiment may be applied to another embodiment, either alone or in combination with other features, unless the feature is otherwise inapplicable or otherwise stated in the other embodiment.

The present invention has been described in terms of the above embodiments, but it should be understood that the above embodiments are for purposes of illustration and description only and are not intended to limit the invention to the scope of the described embodiments. Furthermore, it will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that many variations and modifications may be made in accordance with the teachings of the present invention, which variations and modifications fall within the scope of the present invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. An air-tightness testing device for testing a test piece having a body and a mounting member, a bottom portion of the mounting member being mounted to the body, a top portion of the mounting member having a top port, comprising:

the bracket is arranged on the operating table;

2. The tightness testing device of claim 1, wherein said containment caps are spaced apart and have the same or different heights and sizes.

3. The airtightness testing apparatus according to claim 1, wherein an upper surface of the lower sealing tool is a plane, the lower sealing tool further being provided with an opening forming the receiving portion so that a peripheral portion of the test piece can be lapped to the upper surface when the test piece is received in the opening.

4. The airtightness testing apparatus according to claim 3, wherein the lower sealing tool is provided with a positioning pin extending upward and protruding from the upper surface, the positioning pin being provided around the opening to position the test piece, and the upper sealing tool is provided with a receiving hole corresponding to the positioning pin to receive the positioning pin.

5. The hermetic test apparatus according to claim 1, further comprising:

6. The airtightness testing apparatus according to claim 1, wherein a lower surface of the upper sealing tool is a flat surface, the cavity is recessed upward from the lower surface, and the sealing cover does not protrude from the lower surface.

7. The airtightness testing apparatus according to claim 1, wherein the upper sealing tool is provided with a sealing ring at a peripheral portion of the cavity to be sealingly connected at a peripheral portion of the test piece.

8. The gas-tight test apparatus according to claim 1, further comprising a gas-tight tester connected to the upper sealing tool via a pipeline extending into the cavity to input compressed gas to the test space.

9. The airtightness testing apparatus according to claim 8, wherein a control unit is provided in the airtightness tester, and the control unit is configured to compare a measured pressure of the test piece with a predetermined pressure determined in accordance with a pressure of a standard piece measured by the airtightness testing apparatus to determine whether the test piece leaks.

10. The hermetic test apparatus according to claim 9, wherein the control unit is further configured to store predetermined pressures corresponding to different standard pieces, and to associate the corresponding predetermined pressures according to the test piece.