JP2002263435A - Low humidity storage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a weak point of the conventional low humidity storage that it is difficult to manage articles stored in the low humidity storage and the storage cost is high. SOLUTION: This low humidity storage has a display part arranged at the position related to the place to store an article to be dehumidified for displaying such a value as a dehumidifying time necessary after stored as is obtained by multiplying the time taken for the article to expose in the atmosphere before stored by the prescribed magnification to be decided according to a kind of the article and a reporting means having a timer for reporting the lapes of the dehumidifying time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-humidity storage,
The present invention relates to a low-humidity storage capable of managing storage time of stored articles.

[0002]

2. Description of the Related Art Generally, when an IC package used for an electronic device is mounted on a printed wiring board and reflow soldering is performed, it is heated at about 250 ° C. for about 150 seconds by an infrared heater or the like.

[0003] At this time, if moisture is contained in the molding resin of the IC package, the moisture evaporates instantaneously, and due to the steam pressure, the die pad portion inside the IC package and the molding resin are separated at the interface, and the steam is discharged to the outside. At this time, cracks enter the mold resin, causing various complaints.

[0004] The moisture content of this IC package is expressed by weight.
If the content is 0.15% or more, cracks occur in a state of almost 100%.

Therefore, on the shipping side of the IC package, the IC package is placed in an aluminum pack which has been baked so as not to adsorb moisture, and the humidity indicator card which changes color when moisture is absorbed is sealed together with a desiccant before shipping. The guaranteed time of exposure to air after opening this aluminum pack varies from IC package to IC package, but is about 24 to 72 hours.
The user opens the aluminum pack to mount this IC package and attaches it to the mounter. The surplus IC package is stored in a low humidity storage to prevent moisture absorption.

[0006] Conventionally, Japanese Patent No. 3060168 discloses a device provided with means for indicating a dehumidifying time required for stored articles.

[0007]

However, in the above-mentioned low-humidity storage, a constant value determined according to the type of the article is used as the necessary dehumidification time, and is independent of the time of exposure of the article to the atmosphere. Was.

However, as a result of various experiments and studies, the present inventor has found that the actually required dehumidification time is closely related to the type of the article and the above-mentioned atmospheric exposure time, and that the humidity is 5% R.
When using low humidity storage that can be less than H, the goods are IC
In the case of the package, it was found that there was a factor of about 5 between the time of exposure to air and the time of dehumidification required to remove the moisture of the IC package to about 0%.

That is, FIG. 4 shows an IC package at 30 ° C. and 50% RH.
After 8 hours (see the broken line in FIG. 4), 4 hours (see the broken line in FIG. 4), and 2 hours (see the broken line in FIG. 4)
This is a diagram showing the change in the water content (% by weight) of the IC package when the above IC package is stored in a low humidity storage room of 5% RH. Of water decreased to almost 0%.

The present invention has been made based on such findings.

[0011]

SUMMARY OF THE INVENTION The present invention provides a low humidity storage,
Display means for displaying the atmospheric exposure time before storage of the stored articles and the dehumidification time required after storage at a position related to the storage position of the articles, and a notification for notifying that the dehumidification time has elapsed. Means, wherein the dehumidifying time is a value obtained by multiplying the atmospheric exposure time by a predetermined magnification according to the type of the article.

[0012] The notification is made by blinking or color change.

Further, the notification is made by light or voice.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2, reference numeral 1 denotes a low-humidity storage,
Is a shelf board, 3 is an article to be dehumidified placed on the shelf board 2, for example, an IC package, 3 'is a tray containing the IC package, and 4 is, for example, disclosed in JP-A-6-304436. Reference numeral 5 denotes a door provided corresponding to the shelf plate 2, and reference numeral 6 denotes a glass window of the door 5.

In the present invention, as shown in FIG. 1, for each of the shelves 2, the shelves 2 and / or the doors 5 corresponding to the shelves 2 and the inner surface of the low-humidity storage 1 are provided with the shelves. A setting display unit 7 is provided for setting and displaying the exposure time of the IC package 3 placed in the atmosphere 2 to the atmosphere, the required dehumidification time, and the like.

FIG. 3 shows a setting display section 7 according to the present invention, 8 is a number display showing the shelf 2 and each position on the shelf 2,
9 is an article name display, 10 is an air exposure time display, 11 is a reset button for the air exposure time display 10, 12 is a dehumidification time display obtained by multiplying the air exposure time by a magnification determined according to the article, Reference numeral 13 denotes a reset button for the dehumidification time display 12, reference numeral 14 denotes a display of the elapsed time of dehumidification, reference numeral 15 denotes a display unit for the date when the IC package is stored, and reference numeral 16 denotes a reset button for the display unit 15.

The above magnification is set in advance according to the type of the article and the type of the low humidity storage.

Further, it is preferable to display two kinds of values on the dehumidification time display 12. For example, the time for the crack occurrence caution area is set to four times the air exposure time, and the time for the safety area is five times the air exposure time, and each time is displayed on the dehumidification time display 12. Preferably, a light or audio signal is generated when the time has elapsed.

Also, for example, the time of air exposure
If it is less than 4 times, the water content near the crack occurrence caution area is displayed in red, if it is more than 4 times and less than 5 times the air exposure time it is displayed in yellow, and if it is more than 5 times the air exposure time, it is sufficient Displayed in green or the like to indicate that the vehicle is in the safety area. In this way, the article at the shelf position where the green lamp is lit can be taken out and used with confidence.

[0021]

As described above, the low-humidity storage of the present invention has a great advantage in that it can be easily and reliably managed according to the required dehumidifying time for each article. .

[Brief description of the drawings]

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

FIG. 2 is a side view of the low humidity storage of the present invention.

FIG. 3 is an explanatory diagram of a control meter in the low humidity storage of the present invention.

FIG. 4 is a diagram illustrating a dehumidification state of an IC package by a low humidity storage.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Low humidity storage 2 Shelf 3 IC package 3 'tray 4 Dehumidifier 5 Door 6 Glass window 7 Setting display part 8 Number display 9 Article name display 10 Air exposure time display 11 Reset button 12 Dehumidification time display 13 Reset button 14 Dehumidification Elapsed time display 15 Date display 16 Reset button

Claims (3)

[Claims] 1. A display means for displaying, at a position related to a storage position of an article, an atmospheric exposure time before storage of the stored article and a dehumidification time required after the storage, and the dehumidification time has elapsed. And a notifying means for notifying the user of the fact that the dehumidifying time is a value obtained by multiplying the atmospheric exposure time by a predetermined magnification according to the type of the article. 2. The low humidity storage according to claim 1, wherein the notification is made by blinking or color change. 3. The low humidity storage according to claim 1, wherein the notification is made by light or sound.