VEHICLE LIQUID LEVEL MONITOR FOR PASSENGER PROTECTION INSTALLATIONS

• US 3,781,788 A
• Filed: 03/24/1972
• Issued: 12/25/1973
• Est. Priority Date: 03/25/1971
• Status: Expired due to Term

• Current Assignee: Gerhard Schiesterl, Hans-Ulrich Kuhn
• Original Assignee: Gerhard Schiesterl, Hans-Ulrich Kuhn
• Inventors: Schiesterl, Gerhard, Kuhn, Hans-Ulrich
• Primary Examiner(s): Waring, Alvin H.
• Application Number:
  US05/237,720
• Time in Patent Office: 641 Days
• Field of Search: 340/52H,53,59,244 200/61.45 180/103,104
• US Class Current: 280/728.1
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence

Abstract

A passenger protection installation for vehicles, especially for motor vehicles, which includes at least one air bag that is adapted to be inflated when the vehicle exceeds a predetermined deceleration value, by means of a pressure gas that is developed from a liquefied gas within a pressure gas producer; the pressure gas producer includes a tank for the liquefied gas whereby at least one electrode is provided in the tank which, in relation to a predetermined minimum level of the liquefied gas in the tank, is electrically conductive with respect to the conductive liquefied gas only above this level and at least in its area directly adjacent thereto; when the tank is filled above its minimum level, the electrode is conductively connected by way of the liquefied gas with a connecting element, such as a second electrode, which in turn is connected with a shifting element that closes a further circuit containing an indicating device and/or a control device when the first circuit is interrupted.

Claims

1. A passenger protective installation for vehicles, especially motor vehicles, which comprises at least one air bag means adapted to be inflated by means of pressure gas when the vehicle exceeds a predetermined deceleration value, the pressure gas being developed from liquefied gas in a pressure gas producer means which includes at least one tank means for a liquefied gas, characterized in that a first circuit means is provided including first and second electrode means arranged in the tank means, said first electrode means in relation to a predetermined minimum level in the tank means being electrically conductive with respect to an electrically conductive liquefied gas exclusively above said predetermined level and at least in the area directly adjacent thereto, said second electrode means being electrically conductive with respect to the liquefied gas at least partially below said predetermined minimum level, said first and second electrode means being in electrically conductive connection in the first circuit means by way of the liquefied gas when the tank means is filled above its minimum level, one of said first and second electrode means being operatively connected with a switching means, said switching means being operatively connected with a further circuit means containing monitoring means, said further circuit means being rendered operable to activate the monitoring means upon interruption of the first circuit means when the level of the liquefied gas falls below said predetermined minimum level.

2. A passenger protective installation according to claim 1, characterized in that said monitoring means includes an indicating device.

3. A passenger protective installation according to claim 1, characterized in that the monitoring means includes a control device.

4. A passenger protective installation according to claim 1, characterized in that at least one of the electrode means starts from the bottom side of the tank means and is insulated within the area thereof disposed between the bottom side of the tank means and the predetermined minimum level of the liquefied gas.

5. A passenger protective installation according to claim 1, characterized in that at least one of the electrode means is arranged starting from the top side of the tank means above the predetermined minimum level of the liquefied gas.

6. A passenger prOtective installation according to claim 1, characterized in that at least a portion of the section of at least one of the electrode means which is conductive with respect to the liquefied gas, extends substantially parallel to the liquid level.

7. A passenger protective installation according to claim 1, characterized in that the first and second electrode means are disposed lying adjacent one another.

8. A passenger protective installation according to claim 1, characterized in that a normally closed contact relay means is provided as switching means which is de-energized upon interruption of the first circuit means.

9. A passenger protective installation according to claim 1, characterized in that a lamp is provided as indicating instrument for the monitoring means.

10. A passenger protective installation according to claim 1, characterized in that the liquefied gas is provided with an additive effecting the electrical conductivity thereof.

11. A passenger protective installation according to claim 1, in which the gas is converted from its liquid into its gaseous condition by the supply of heat, characterized in that an explosive cartridge means is arranged in the tank means which is ignitable by way of a sensor means in dependence on the predetermined deceleration value, and in that a further monitoring means is coordinated to the sensor means, the further circuit means being operable to be actuated also by said further monitoring means.

12. A passenger protective installation according to claim 11, characterized in that the further circuit means is adapted to be closed by said further monitoring means.

13. A passenger protective installation according to claim 12, characterized in that a lamp is provided as indicating instrument for the monitoring means.

14. A passenger protective installation according to claim 11, characterized in that at least one of said electrode means extends from the bottom side of the tank means.

15. A passenger protective installation according to claim 11, characterized in that at least one of said electrode means extends from the top side of the tank means.

16. A passenger protective installation according to claim 11, characterized in that said first and second electrode means are disposed in side-by-side relation.