The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 16, 1976
Filed:
Nov. 01, 1974
Richard L Jenne, Attleboro, MA (US);
Leo Marcoux, Rehoboth, MA (US);
Thomas E Evans, Rehoboth, MA (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A system for monitoring usage of seat belt means in a motor vehicle includes electrically operable visual signaling means and electrically operable audible signaling means. A first switch is operable in response to initiation of motor vehicle operation for connecting the signaling means to an electrical power supply in the vehicle. An additional switch is operable in response to fastening of the vehicle seat belt means for preventing operation of the audible signaling means when the seat belt means are properly fastened. A pair of first electrical resistors of positive temperature coefficient of resistivity which are adapted to display a sharp increase in resistivity when heated to predetermined operating temperatures are arranged in series between the vehicle power supply and the visual and audible signaling means respectively for terminating operation of said signaling means individually when said first resistors are heated to said operating temperatures. A third electrical resistor of positive temperature coefficient of resistivity which displays a sharp increase in resistivity when heated to a predetermined operating temperature is arranged to be connected to said vehicle power supply on initiation of vehicle operation and is disposed in selected heat-transfer relation to said first resistors for heating said first resistors to their operating temperatures with a selected time delay after initiation of motor vehicle operation, thereby to terminate operation of said signaling means after said time delay even if said vehicle seat belt means have not been properly fastened. A control device particularly adapted for use in such seat belt monitoring systems includes a casing having a cavity and having a plurality of slots extending into the casing cavity. Three terminals are disposed in respective casing slots to dispose one end of each terminal within said cavity. The pair of first resistor elements are disposed in the casing cavity to electrically engage respective terminals and the second resistor is disposed in the cavity in heat-transfer relation to the first resistors to electrically engage each of the first resistors and to electrically engage a third terminal. A fourth terminal disposed in a fourth casing slot also electrically engages the second resistor and a cover secured to the casing retains the resistors and terminals in assembled relation. This control device is therefore adapted to be conveniently combined with existing automotive switch means to economically provide seat belt monitoring systems as above-described.