JP2008224485A - Siloxane endurance testing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate development of a contact structure and material where a contact failure of an electrical contact section arising from siloxane hardly occurs. <P>SOLUTION: This siloxane endurance testing machine 1 comprises a siloxane gas generator 10, a test room 20, a siloxane concentration measurement section 30, and a control section 40. The siloxane gas generator 10 has two mass flow controllers 12 and 13 and a bubbler 11. The siloxane concentration measurement section 30 measures siloxane concentration in a test area of the test room 20. The control section 40, using the measurement result, controls the mass flow controllers 12 and 13 of the siloxane gas generator 10. Thus, the siloxane concentration in the test area can be set to a desired concentration. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a siloxane durability tester.

  Siloxane (low molecular cyclic siloxane) is easily gasified at room temperature, and becomes a combination of silica and carbide by receiving electric energy at the electric contact portion. Silica is an insulating material and has a property of firmly adhering to contacts, and thus causes contact failure of electrical contact portions (see Patent Document 1).

Japanese Patent Laid-Open No. 2006-124489

  Siloxane is contained in a large amount in familiar products such as general plastics, synthetic rubbers, adhesives, cosmetics, and hair sprays, which causes problems in familiar electrical products.

  In particular, in the case of automobiles, the interior of a car parked in summer is heated and sealed, so a large amount of siloxane is gasified from interior materials, adhesives, and various plastic materials. When an electronic device is exposed to a very high concentration of siloxane, silica, which is an insulator, is generated by electrical energy at a contact portion when the switch is turned on, and a contact failure occurs. Also, in the engine room, siloxane is gasified due to heat generated by the engine, and the same contact failure occurs. These cause poor contact not only at the operating contacts of the equipment but also at various connectors. This is due to the fact that the contact of the connector moves while being energized by the vibration of the automobile in the presence of siloxane.

  Against this backdrop of electrical contact failures, manufacturers are forced to develop contact structures and materials that can withstand siloxane.

  An object of the present invention is to provide a technique for facilitating the development of a contact structure and a material in which contact failure of an electrical contact portion due to siloxane is unlikely to occur.

  A siloxane durability tester according to the present invention includes a siloxane gas generator that generates a siloxane gas in a variable concentration, a sealed test area to which the siloxane gas generated by the siloxane gas generator is supplied, and an inside of the test area. A siloxane concentration sensor for measuring the siloxane concentration of the siloxane gas, and a control means for controlling the siloxane gas generator based on the siloxane concentration detected by the siloxane concentration sensor so that the siloxane concentration in the test area becomes a predetermined concentration. I have.

  According to the present invention, since the siloxane concentration in the test area can be set to a desired concentration, it is easy to develop a contact structure and a material in which a contact failure of an electric contact portion caused by siloxane hardly occurs.

  A bubbler for generating a saturated siloxane gas by bubbling a siloxane liquid stored in a siloxane storage tank with a first gas not containing siloxane, and a flow rate of the first gas supplied to the bubbler. The flow rate is adjusted by the first flow rate adjusting mechanism for adjusting the flow rate, the second flow rate adjusting mechanism for adjusting the flow rate of the second gas not containing siloxane, the saturated siloxane gas generated in the bubbler, and the second flow rate adjusting mechanism. And a supply gas flow path for supplying a mixed gas mixed with the second gas to the test area. Thereby, the siloxane standard gas which is not commercially available can be generated from the commercially available siloxane liquid so as to have a desired concentration.

  In the siloxane durability tester of the present invention, the flow rate is adjusted by the third flow rate adjustment mechanism that adjusts the flow rate of the third gas not containing siloxane, the sampling gas extracted from the test area, and the third flow rate adjustment mechanism. It is preferable to further include a measurement gas flow path for supplying a mixed gas mixed with the third gas to the siloxane concentration sensor. As a result, even if the concentration of the sampling gas extracted from the test area is higher than the measurable range of the siloxane concentration sensor, the concentration of the sampling gas can be measured by supplying the diluted gas to the siloxane concentration sensor. It becomes possible.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram of a siloxane durability tester according to an embodiment of the present invention. The siloxane durability tester 1 shown in FIG. 1 is roughly divided into four parts: a siloxane gas generator 10, a test chamber 20 that defines a sealed test area, a siloxane concentration measurement unit 30, and a control unit 40. The

  The siloxane gas generator 10 includes a bubbler 11 that generates siloxane gas by a bubbler method. The bubbler 11 is supplied with nitrogen gas (N2) containing no siloxane from the mass flow controller 12. The mass flow controller 12 adjusts the nitrogen gas supplied to the bubbler 11 according to the control output from the control unit 40.

  FIG. 2 shows a detailed view of the bubbler. The bubbler 11 includes a siloxane storage tank 101 in which a siloxane liquid is stored. In the siloxane storage tank 101, it is a hot water part in which the siloxane liquid is stored up to the vicinity of the central part thereof. The portion other than the siloxane liquid inside the siloxane reservoir 101 is a gas phase portion filled with siloxane gas.

  In the vicinity of the lower end of the siloxane reservoir 101, an inlet 101 a for nitrogen gas whose flow rate is adjusted by the mass flow controller 12 is provided. The siloxane gas generated when the nitrogen gas supplied from the inlet 101a to the hot water portion of the siloxane storage tank 101 becomes bubbles and rises in the hot water portion is stored in the gas phase portion. Siloxane gas (siloxane saturated vapor) stored in the gas phase portion is discharged from an outlet 101 b provided at the upper end of the siloxane reservoir 101.

  A temperature sensor 103 is attached to the siloxane reservoir 101. The temperature sensor 103 is inserted from the ceiling of the siloxane reservoir 101 and passes through the gas phase portion, and the tip reaches the hot water portion. The temperature sensor 103 has thermocouples 103a and 103b at positions corresponding to the gas phase portion and the hot water portion, respectively, and performs temperature detection in each of the thermocouples 103a and 103b. In general, the siloxane gas temperature in the gas phase is the same as the siloxane liquid temperature in the hot water.

  A U-shaped heater 105 is disposed in the hot water section. The heater 105 raises the siloxane liquid temperature of the hot water part according to the control output from the control part 40.

  The bubbler 11 has a temperature adjustment device 110 that adjusts the temperatures of the siloxane gas in the gas phase and the siloxane liquid in the hot water. The temperature control device 110 is a circulation line through which water circulates, and includes a water jacket 111 that surrounds a portion corresponding to the gas phase portion of the siloxane reservoir 101. The water jacket 111 adjusts the siloxane gas temperature in the gas phase portion. In addition, the temperature control device 110 includes a heat exchanger 113 that performs heat exchange between the water discharged from the water jacket 111 and the cooling water supplied from the outside, and a U that is provided in the hot water section and adjusts the temperature of the siloxane liquid. A tubular serpentine tube 115, a pump 117, and a heater 119 for heating water supplied to the water jacket 111 are included. Further, the water temperature in the water jacket 111 is measured by the water temperature sensor 120. Between the water jacket 111 and the heat exchanger 113, a three-way valve 112 for adjusting the amount of water flowing to the heat exchanger 113 is disposed.

  The heater 105 and the temperature control device 110 in the bubbler 11 are controlled according to the control output from the control unit 40. Thereby, the temperature of the siloxane gas discharged | emitted from the exit 101b of the siloxane storage tank 101 can be adjusted.

  Since the siloxane durability tester 1 according to the present embodiment has the bubbler 11, a siloxane standard gas not commercially available can be generated from the commercially available siloxane liquid so as to have a desired concentration.

  The siloxane gas generator 10 includes a mass flow controller 13. The mass flow controller 13 adjusts the flow rate of nitrogen gas supplied from the same supply source as the nitrogen gas supplied to the mass flow controller 12.

  In the siloxane gas generator 10, the siloxane gas generated by the bubbler 11 and the nitrogen gas whose flow rate is adjusted by the mass flow controller 13 are mixed at the mixing point 14 a, and the mixed gas is supplied to the test area in the test chamber 20. Such a supply gas flow path 14 is provided.

  Heaters 15 and 16 are disposed between the mass flow controller 13 and the mixing point 14a and between the bubbler 11 and the mixing point 14a, respectively. These heaters 15 and 16 heat nitrogen gas and siloxane gas, thereby preventing these gases from being liquefied (condensed) during mixing. The space between the mixing point 14 a of the supply gas flow path 14 and the test chamber 20 is covered with a heat retaining heater 17. This prevents the mixed gas from being liquefied before reaching the test chamber 20.

  As described above, the siloxane gas generator 10 supplies the siloxane gas having a necessary concentration to the test chamber 20 by mixing the nitrogen gas and the siloxane gas after the nitrogen gas is divided.

  The test chamber 20 that is a sealed container is made of a material that does not contain siloxane (for example, metal). Metal (SUS) is also used for packing used in a joint portion between the test chamber 20 and a pipe line connected thereto.

  In the test chamber 20, a fan 21, a heater 22 and a cooler 23 are arranged for adjusting the environment of the test area. Thereby, the temperature in a test area can be adjusted to desired temperature. For example, it is preferable that the control unit 40 has a high-temperature operation function for increasing the temperature in the test room 20 so that the environment in the automobile room in summer can be reproduced. In this example, a temperature environment from room temperature to 120 ° C. can be provided. A test at about 80 ° C. is common. The siloxane gas concentration in the test area is about 10 to 500 ppm in the normal test and about 1000 to 5000 ppm in the accelerated test.

  A cassette-exchangeable siloxane adsorption unit 25 is connected to the test chamber 20 so that the siloxane zero state can be reproduced at the start of the test. The siloxane adsorption unit 25 is obtained by processing activated carbon fiber cloth into a filter shape, and achieves both an increase in effective adsorption area and a compact unit 25.

  The siloxane concentration measuring unit 30 includes a siloxane concentration sensor 31 and a mass flow controller 32. The mass flow controller 32 adjusts the flow rate of nitrogen gas supplied from the same supply source as the nitrogen gas supplied to the mass flow controllers 12 and 13. In the siloxane concentration measuring unit 30, the siloxane gas overflowing from the test chamber 20 and the nitrogen gas whose flow rate is adjusted by the mass flow controller 32 are mixed at the mixing point 33 a, and the mixed gas is supplied to the siloxane concentration sensor 31. Such a measurement gas flow path 33 is provided. The siloxane concentration sensor 31 measures the concentration of the supplied mixed gas.

  A heater 35 is disposed between the mixing point 33 a of the measurement gas flow path 33 and the mass flow controller 32. The heater 35 prevents the nitrogen gas from being liquefied (condensed) during mixing by heating the nitrogen gas. Between the mixing point 33a of the measurement gas flow path 33 and the test chamber 20, between the mixing point 33a and the heater 35, and between the mixing point 33a and the siloxane concentration sensor 31, are covered with a heat retaining heater 37. It has been broken. This prevents the gas from being liquefied before reaching the siloxane concentration sensor 31.

  Thus, since the mixed gas of the sampling gas of the siloxane gas extracted from the test area and the nitrogen gas whose flow rate is adjusted by the mass flow controller 32 is supplied to the siloxane concentration sensor 31, it is extracted from the test area. Even if the concentration of the sampling gas is higher than the measurable range of the siloxane concentration sensor 31, the concentration of the sampling gas can be measured by supplying the diluted gas to the siloxane concentration sensor 31.

  The detection output of the siloxane concentration sensor 31 is supplied to the control unit 40. The control unit 40 controls the mass flow controllers 12 and 13 by a control output generated based on feedback control. Thereby, since the flow rate per unit time of the gas flowing downstream from the mass flow controllers 12 and 13 is adjusted, the siloxane concentration in the test area can be set to a desired concentration. Therefore, it becomes easy to develop a contact structure and a material in which the contact failure of the electrical contact portion due to siloxane hardly occurs in the test area.

  Moreover, the control part 40 controls the heater 105 and the temperature control apparatus 110 in the bubbler 11 with a control output. Thereby, control of the siloxane gas temperature discharged | emitted from the bubbler 11 is attained. In addition, various outputs such as the outputs of the temperature sensor 103 and the water temperature sensor 120 are supplied to the control unit 40. And the control part 40 controls the whole operation | movement of the siloxane durability tester 1 based on these outputs.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made to the above-described embodiments as long as they are described in the claims. It is possible to apply. For example, siloxane gas may be generated by a method other than a bubbler. The siloxane gas concentration in the test area may be adjusted by a method other than adjusting the flow rate of the mass flow controller. The three mass flow controllers 12, 13, and 32 may be provided with different types of siloxane-free gas.

It is a schematic block diagram of the siloxane durability testing machine which concerns on one embodiment of this invention. FIG. 2 is a detailed view of a bubbler included in the siloxane durability tester shown in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Siloxane endurance test machine 10 Siloxane gas generator 11 Bubbler 12, 13, 32 Mass flow controller 14 Supply gas flow path 15, 16 Heater 20 Test room 25 Siloxane adsorption unit 30 Siloxane concentration measurement part 31 Siloxane concentration sensor 33 Measurement gas flow path 40 Control unit 101 Siloxane reservoir 105 Heater 110 Temperature control device 111 Water jacket

Claims (3)

A siloxane gas generator for generating a siloxane gas with variable concentration;
A sealed test area to which the siloxane gas generated by the siloxane gas generator is supplied;
A siloxane concentration sensor for measuring the siloxane concentration in the test area;
A siloxane durability test comprising a control means for controlling the siloxane gas generator so that the siloxane concentration in the test area becomes a predetermined concentration based on the siloxane concentration detected by the siloxane concentration sensor. Machine. The siloxane gas generator is
A bubbler for generating saturated siloxane gas by bubbling a siloxane liquid stored in a siloxane storage tank with a first gas not containing siloxane;
A first flow rate adjusting mechanism for adjusting a flow rate of the first gas supplied to the bubbler;
A second flow rate adjusting mechanism for adjusting the flow rate of the second gas not containing siloxane;
A supply gas flow path for supplying a mixed gas obtained by mixing the saturated siloxane gas generated in the bubbler and the second gas whose flow rate is adjusted by the second flow rate adjusting mechanism to the test area; The siloxane durability tester according to claim 1, wherein: A third flow rate adjusting mechanism for adjusting the flow rate of the third gas not containing siloxane;
And a measurement gas flow path for supplying a mixed gas obtained by mixing the sampling gas extracted from the test area and the third gas whose flow rate is adjusted by the third flow rate adjusting mechanism to the siloxane concentration sensor. The siloxane durability tester according to claim 1 or 2, wherein

Images