Safety indicating device for flashlights

• US 5,483,228 A
• Filed: 01/31/1994
• Issued: 01/09/1996
• Est. Priority Date: 01/31/1994
• Status: Expired due to Fees

• Current Assignee: Eveready Battery Company Incorporated (Energizer Holdings, Inc.)
• Original Assignee: Eveready Battery Company Incorporated (Energizer Holdings, Inc.)
• Inventors: Foley, Timothy D., Bailey, John C.
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): LIEU, JULIE BICHNGOC
• Application Number:
  US08/188,868
• Time in Patent Office: 708 Days
• Field of Search: 340/632, 340/636, 323/369, 323/294, 323/366, 323/294, 429/90
• US Class Current: 340/632
• CPC Class Codes: G01M 3/045 with electrical detection means
• CPC Class Codes: H01M 10/52 Removing gases inside the secondary cell, e.g. by absorption vent plugs or other mechanical arrangements for facilitating escape of gases H01M50/30
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A safety disconnect device for use in detecting a gas in a confined space, such as a flashlight, comprising the use of a catalytic gas recombination material, such as palladium, in conjunction with a heat-sensitive conductive element connected as a switch, in a circuit containing a power supply so that the heat generated by the reaction of the detected gas with a reactant on the surface of the catalytic material will alter the heat-sensitive conductive element to open the circuit.

Claims

1. A safety device for monitoring gas buildup in a confined interior space of a flashlight container containing a plurality of electrochemical cells, said gas buildup .being due to gases venting from said cells into said confined space of said flashlight container, comprising a catalytic gas recombination material in said confined space of said flashlight container that will facilitate an exothermic reaction between a gas to be monitored and at least one other reactant material;

a heat-sensitive conductive element disposed adjacent to the catalytic gas recombination material;

an electrical circuit comprising power means; and

wherein said heat-sensitive conductive element is connected as a switch means in said circuit so that when a buildup of a predetermined level of gas to be monitored is reached in said confined space of said flashlight container, the exothermic reaction of the reactant with the gas on the surface of the catalytic gas combination material will produce heat that will be detected by the heat-sensitive conductive element and be sufficient to change the heat-sensitive conductive element in the circuit to disconnect the circuit and thereby limit gas buildup in said confined space.

2. The safety device for monitoring gas buildup in a confined space of claim 1 wherein said heat-sensitive conductive element is selected from the group consisting of bimetallic switches, positive temperature coefficient resistors and thermistors.

3. The safety device for monitoring gas buildup in a confined space of claim 1 wherein said catalytic gas recombination material is selected from the group consisting of palladium, palladium alloys, platinum, platinum alloys, rhodium, rhodium alloys, platinum-catalyzed MnO₂, nickel boride, Raney nickel and palladium- catalyzed carbon.

4. The safety device for monitoring gas buildup in a confined space of claim 1 wherein the catalytic gas recombination material is palladium or an alloy of palladium.

5. The safety device for monitoring gas buildup in a confined space of claim 1 wherein the catalytic gas recombination material is a coating on a substrate.

6. The safety device for monitoring gas buildup in a confined space of claim 1 wherein the catalytic gas recombination material is formed into a discrete body.