JPH0638244U - Low humidity storage - Google Patents

Abstract

(57) [Summary] [Purpose] Maintenance and management are easy and a high dehumidification state is secured. [Structure] In a storage cabinet body 1, a closed cabinet 5 that can be opened / closed by an opening / closing door 3, and a water vapor in the raw material air supplied from an air pump 41 are permeated to the outside of a membrane 47 and dried to expel the water vapor. Membrane-type air dryers 29 and 30 equipped with a membrane-type module 31 for taking out air, blowing nozzles 27 that blow dry air from the membrane-type air dryers 29 and 30 into the interior 5, and air in the interior 5 are removed. And a discharge unit 11 having an opening / closing valve 19 for discharging the discharge to the.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a low-humidity storage for storing a sample, such as an IC or an LSI, that does not like moisture until it is mounted.

[0002]

[Prior art]

 In recent years, high-density packaging of semiconductors such as IC and LSI has been rapidly progressing. At that time, when thermal stress such as soldering is applied to the IC, it is almost 100 in the case of the IC containing moisture. Expansion of the die pad and microcracks occur in a state close to%. As a result, the humidity resistance is adversely affected, and the printed wiring is corroded for a long time, which may cause wire dribbling such as wire breakage.

As a countermeasure for this, for example, (1) heat dehumidify the IC every time it is mounted on the surface, or (2) keep it in a desiccator with a moisture adsorbent such as silica gel or zeolite until the time of use. store. (3) In addition, means such as putting in nitrogen gas or (4) or dehumidifying steam with a refrigerator is adopted.

[0004]

[Problems to be solved by the device]

 As described above, in the case of surface-mounted ICs and LSIs, the low humidity condition is maintained by the steps shown in (1) to (4). However, in (1), Is not desirable in terms of workability because the work is very troublesome. In the case of (2), it is necessary to regenerate the saturated water adsorbent once every 6 hours in addition to the fact that the humidity drops to only about 10% and the efficiency is low. Therefore, there is a problem that maintenance and management are very troublesome and the humidity rises up to about 30% during regeneration. Further, in the case of (3), it is costly and not desirable in terms of running cost. In (4), there were drawbacks such as the CFC problem and the size of the device becoming larger.

Therefore, it is an object of the present invention to provide a low-humidity storage cabinet that is easy to maintain and manage and has high dehumidification efficiency.

[0006]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention has a storage cabinet body in which a closed cabinet that can be opened and closed by an opening / closing door and water vapor in raw material air supplied from an air pump are transmitted to the outside of the membrane. Membrane-type air dryer equipped with a membrane-type module that takes out dry air from which steam has been expelled, a blowing nozzle that blows dry air from the membrane-type air dryer into the refrigerator, and an on-off valve that discharges air from the refrigerator to the outside. And a discharge section provided with.

[0007]

[Action]

 According to such a low humidity storage, the raw material air supplied from the air pump passes through the inside of the membrane air dryer. During the passage, the water vapor permeates out of the membrane by the membrane type module, and the dry air from which the water vapor has been expelled is blown out from the blowing nozzle into the chamber.

As a result, a low humidity condition in the refrigerator is secured. In addition, it is easy to maintain and manage because no extra maintenance is required.

[0009]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings of FIGS.

In the figure, reference numeral 1 denotes a storage cabinet body. The front of the storage cabinet body 1 is an opening / closing door 3 that can be opened and closed, and when the opening / closing door 3 is fully closed, a closed storage room 5 is secured.

A plurality of shelves 7 on which samples such as ICs and LSIs are placed, a temperature / humidity sensor 9, and a discharge unit 11 are provided in the interior 5.

The shelf plate 7 is detachably attached to the shelf receiving column 13 so that a parts cassette rack or the like can be placed in correspondence with the packaging form of IC, LSI and the like.

The temperature / humidity sensor 9 monitors the temperature and humidity of the interior 5, and the display unit 15 on the surface displays the interior temperature and the interior humidity so that the operator can directly check them. ing.

The discharge part 11 is provided with an opening / closing valve 19 in a cylindrical part 17 formed in a cylindrical shape as shown in FIG. The on-off valve 19 is provided with a plurality of window holes 23 corresponding to the window holes 21 provided on the cylindrical portion 17 side. By rotating the on-off valve 19, the opening amount of the window hole 21 is controlled. When the window hole 21 and the window hole 23 are completely misaligned, they are fully closed. Further, when the positions of the window holes 21 and 23 coincide with each other, the fully opened state can be obtained.

On the other hand, a heater 25, a blowing nozzle 27, and film type air dryers 29 and 30 are arranged at the bottom of the storage body 1.

The membrane-type air dryers 29 and 30 are for removing water vapor by the membrane-type module 31 and taking out dry air. As shown in FIG. 2, the second membrane air dryer 30 with respect to the first membrane air dryer 29 is controlled by opening / closing the solenoid valve 33 and the speed control valve 35, for example, at the beginning of operation, or When the opening / closing door 3 is opened, the solenoid valve 33 is "opened" so that the first and second membrane air dryers 29 and 30 can be used in a full operation state. When the humidity reaches a predetermined level, the solenoid valve 33 is "closed" so that the first membrane air dryer 29 can reduce the capacity to half.

As shown in FIG. 3, the membrane type module 31 has a hollow fiber 37 (outer diameter of 500 to 600 μm) made of a fluoropolymer having a property of not only having a high water permeation rate but also selectively permeating water molecules. ) Are bundled and stored in a metal case 39, which is a hollow fiber type.

As shown in FIG. 5, the hollow fibers 37 have air with different partial pressures of water vapor on the inside and the outside of the hollow fiber membrane 47 (for example, wet air on the inner supply side and permeate side on the outer side). The presence of (dry air) causes water molecules to move through the membrane 47 due to the partial pressure difference of water vapor, so that dry air from which water vapor has been removed can be obtained on the supply side.

In this case, Po: water vapor permeability coefficient (cm3 / cm2, sec, cmHg) An: membrane area (cm2) Pf: supply side water vapor partial pressure (cmHg) Pp: permeation side water vapor partial pressure (cmHg) The water vapor transmission rate Qv is calculated by the following equation.

Qv = Po × Am × (Pf−Pp) [cm ³ / sec] On the other hand, one end of the metal case 39 is provided with an intake port 43 to which the raw material air from the air pump 41 is supplied, and the other end thereof is An outlet 45 for taking out the dry air is provided. The raw material air from the outlet 43 is passed through the hollow fiber membrane 47 of each hollow fiber 37 by a sealing material 49 between the hollow fibers 37. It is sealed. A purge air intake port 51 and a purge air intake port 53 are provided between the seal material 49 and the metal case 39, respectively. The purge air intake port 51 is connected to the intake port 45 for extracting the drying air via a pipe 55, and the speed control valve 57 provided in the pipe 55 is controlled to control the intake amount of the purge air. It is set. The other purge air outlet 51 is opened to the outside air via a pipe 59 and is released into the atmosphere.

As a result, in the membrane type module 31, the wet air passes through the hollow fiber membrane 47, while the dry air passes through the outside of each hollow fiber 37, so that a partial pressure difference of water vapor between inside and outside is created. Then, the water vapor permeated from the hollow fiber membrane 47 to the outside is discharged together with the purge air.

The blow-out nozzle 27 is in continuous communication with the outlet 45 of the membrane type air dryer 29, 30 and blows out into the refrigerator via a large number of jet outlets 63 provided on the floor plate 61 of the refrigerator 5. It is supposed to be.

The heater 25 is located between the floor plate 61 and the blowing nozzle 27, and the dry air blown from the blowing nozzle 27 is raised to a predetermined temperature by touching the heater 25. It is designed to be controlled and controlled to a predetermined temperature by an external control unit.

In FIG. 2, reference numeral 65 is a filter, and 67 is a pressure gauge.

According to the low-humidity storage configured as described above, the raw material air supplied by the air pump 41 passes through the membrane air dryers 29 and 30. During this passage, the water vapor permeates out of the membrane 47 by the membrane module 31 and is discharged into the atmosphere together with the purge air. On the other hand, the dry air from which the water vapor has been removed is sent from the blowing nozzle 27 into the inside 5. Therefore, the low humidity condition can be stably obtained for a long period of time in the interior 5, and the extra maintenance is not required, and the maintenance and management are easy.

[0026]

[Effect of device]

 As described above, according to the low-humidity storage of the present invention, a low-humidity state can be stably obtained for a long period of time, and no extra maintenance is required. Therefore, maintenance and management are difficult. It will be excellent.

[Brief description of drawings]

FIG. 1 is a side view of a low humidity storage according to the present invention.

[Fig. 2] Piping system diagram of membrane air dryer

[Fig. 3] Sectional view of membrane air dryer

FIG. 4 is a schematic plan view of a discharge section.

FIG. 5 is an explanatory diagram of a water vapor transmission principle.

[Explanation of symbols]

 1 Storage Main Body 3 Opening / Closing Door 5 Inside 11 Discharging Section 19 Opening / Closing Valve 27 Blowing Nozzle 29/30 Membrane Air Dryer 31 Membrane Module

Claims (1)

[Scope of utility model registration request] 1. An inside of the storage cabinet which is closed and opened by an opening / closing door, and a vapor in the raw material air supplied from an air pump is permeated to the outside of the membrane, and dry air from which the vapor is expelled is taken out. Provided with a membrane air dryer equipped with a membrane module, a blow-out nozzle that blows dry air from the membrane air dryer into the refrigerator, and an outlet with an on-off valve that discharges the air in the refrigerator to the outside. A low-humidity storage cabinet characterized by that.