Claims
- 1. A depression container comprising:a vessel including a compartment with an open end; a cover for enclosing the open end of the vessel and thus sealing the compartment; an air pump for drawing air out of the compartment of the vessel; and a pressure-activated switch for controlling on/off of the air pump; the pressure-activated switch being capable of detecting an internal pressure in the compartment of the vessel, the air pump being turned on when the internal pressure is higher than a predetermined first pressure value, the air pump being turned off when the internal pressure is lower than a predetermined second pressure value that is smaller than the predetermined first pressure value; the pressure-activated switch and the air pump being powered by an A.C. power source.
- 2. The depression container as claimed in claim 1, wherein the cover comprises a space for receiving the pressure-activated switch and the air pump.
- 3. The depression container as claimed in claim 1, further comprising means for inputting the predetermined first pressure value and the predetermined second pressure value.
- 4. The depression container as claimed in claim 1, further comprising means for inputting a name of an article to be preserved in the vessel.
- 5. The depression container as claimed in claim 1, further comprising a switch for controlling/off of the pressure-activated switch.
- 6. A depression container comprising:a vessel including a compartment with an open end; a cover for enclosing the open end of the vessel and thus sealing the compartment; an air pump for drawing air out of the compartment of the vessel; and a pressure-activated switch for controlling on/off of the air pump; the pressure-activated switch detecting a pressure difference resulting from a closing motion of the cover on the vessel and turning the air pump on to thereby draw air out of the compartment of the vessel, the air pump being turned off when an internal pressure in the compartment detected by the pressure-activated switch is lower than a predetermined pressure value; the pressure-activated switch and the air pump being powered by an A.C. power source.
- 7. The depression container as claimed in claim 6, wherein the pressure-activated switch comprises a differential type pressure transducer and a control chip electrically connected to the air pump, the pressure transducer having a sensor extended into the compartment of the vessel for detecting the internal pressure in the compartment and outputting a voltage to the control chip in response to a difference between a reference pressure and the internal pressure detected by the sensor.
- 8. The depression container as claimed in claim 7, wherein the reference pressure is the atmosphere pressure.
- 9. The depression container as claimed in claim 7, wherein the cover comprises a space for receiving the pressure-activated switch and the air pump.
- 10. The depression container as claimed in claim 7, further comprising means for inputting the predetermined pressure value.
- 11. The depression container as claimed in claim 7, further comprising means for inputting a name of an article to be preserved in the vessel.
- 12. The depression container as claimed in claim 9, wherein the cover comprises a sealing plate securely mounted therein for supporting the air pump and the pressure-activated switch, the sealing plate including a first through-hole and a second through-hole that are communicated with the compartment, a first airtight sleeve being extended through the first through-hole, an air duct extending from the air pump into the compartment via the first airtight sleeve, a second airtight sleeve being extended through the second through-hole, the sensor being extended into the compartment via the second airtight sleeve.
- 13. The depression container as claimed in claim 12, wherein the sealing plate further comprises a first cylindrical wall surrounding the first through-hole and a second cylindrical wall surrounding the second through-hole, the first cylindrical wall including an inner threading, the air pump including an outer threading for threading engagement with the inner threading of the first cylindrical wall, the second cylindrical wall including an inner threading, the pressure-activated switch including an outer threading for threading engagement with the inner threading of the second cylindrical wall.
- 14. The depression container as claimed in claim 7, further comprising a switch movable between a first position for automatic operation in which the air pump draws air out of the compartment of the vessel upon the pressure difference generated as a result of the closing motion of the cover and a second position for manual operation in which the air pump is activated to draw air out of the compartment when the detected internal pressure in the compartment is higher than a predetermined second pressure value.
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation-in-part application of U.S. patent application Ser. No. 09/883,813 filed on Jun. 18, 2001, now U.S. Pat. No. 6,470,924.
US Referenced Citations (7)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/883813 |
Jun 2001 |
US |
Child |
10/230939 |
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US |