ACTIVE FUEL CAP SENSOR USING MAGNETIC IMPULSE DETECTION

• US 20030102976A1
• Filed: 12/02/2002
• Published: 06/05/2003
• Est. Priority Date: 12/03/2001
• Status: Abandoned Application

• Current Assignee: Roger Lavallee
• Original Assignee: Roger Lavallee
• Inventors: Lavallee, Roger
• Application Number:
  US10/065,935
• Publication Number:
  US 20030102976A1
• Time in Patent Office: Days
• US Class Current: 340/687
• CPC Class Codes: B60K 15/0406 Filler caps for fuel tanks
• CPC Class Codes: B60K 2015/0319 with electronic systems, e.g. for controlling fuelling or venting

Abstract

Abstract of Disclosure

An apparatus and circuit for monitoring the closed position of a fuel cap relative to a tank connection pipe . The fuel cap has a ratchet torque limiter for controlling the tightening of the fuel cap to the tank connection pipe. A magnet is connected to the fuel cap and a magnetic switch, such as a reed switch, is connected to the tank connection pipe or proximal thereto. The movement of the magnet relative to the magnetic switch, indicating a locked fuel cap condition, is sensed by an abrupt change in magnetic field strength of the magnet. When releasing members snap over the cams therein, a current pulse is induced in a pickup coil . This current pulse is sensed and a logic level high voltage is produced corresponding to a tightened fuel cap condition. A dashboard lamp is then extinguished indicated that the fuel cap is safely and securely tightened.

Claims

1. An apparatus for monitoring the closed position of a fuel cap relative to a tank connection pipe, comprising:

a fuel cap;

a tank connection pipe having a wall;

ratchet means connected to the fuel cap for controlling tightening of the fuel cap to the tank connection pipe;

a magnet connected to the fuel cap;

a magnetic switch connected to the tank connection pipe; and

means for sensing abrupt movement of the magnet relative to the magnetic switch, indicating a locked fuel cap condition, by sensing an abrupt change in magnetic field strength of the magnet.

2. The apparatus of Claim 1, wherein the magnetic switch is a reed switch.

3. The apparatus of Claim 2, wherein the reed switch is a form A, normally open, reed switch.

4. The apparatus of Claim 1, wherein the magnetic switch is embedded within the wall of the tank connection pipe.

5. The apparatus of Claim 1, wherein the fuel cap includes male threading engageable with female threading on an interior surface of the wall of the tank connection pipe.

6. A method for monitoring the closed position of a fuel cap relative to a tank connection pipe, comprising the steps of:

providing a fuel cap;

providing a tank connection pipe;

providing a magnet connected to the fuel cap;

providing a magnetic switch connected to the tank connection pipe; and

sensing abrupt movement of the magnet relative to the magnetic switch, indicating a tightened fuel cap condition, by sensing an abrupt change in magnetic field strength of the magnet.

7. The method of Claim 6, wherein the step of sensing abrupt movement further comprises the steps of:

providing a circuit with a pickup coil and an output;

snapping the fuel cap into a rest condition;

inducing a current pulse in the pickup coil;

sensing the current pulse;

producing a logic level high voltage at the output; and

displaying an indication of a tightened fuel cap condition.