US 12,380,795 B2
Safety circuit, device and method
Matthew Shannon, Salisbury, NC (US); Wesley M. Barbee, Oxboro, NC (US); Craig M. Parkulo, Midland, NC (US); Ronnie G. Durham, Monroe, NC (US); Michael R. Oliva, Fair Oaks Ranch, TX (US); Paul M. Rathke, Swannanoa, NC (US); and Brian Minier, Raleigh, NC (US)
Assigned to 3M Innovative Properties Company, St. Paul, MN (US)
Appl. No. 18/043,924
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
PCT Filed Aug. 30, 2021, PCT No. PCT/IB2021/057917
§ 371(c)(1), (2) Date Mar. 3, 2023,
PCT Pub. No. WO2022/058825, PCT Pub. Date Mar. 24, 2022.
Claims priority of provisional application 63/080,058, filed on Sep. 18, 2020.
Prior Publication US 2023/0326326 A1, Oct. 12, 2023
Int. Cl. G08B 25/01 (2006.01); G08B 21/04 (2006.01)
CPC G08B 25/016 (2013.01) [G08B 21/0438 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A safety circuit for a Personal Alert Safety System (PASS) device, the safety circuit comprising:
a safety logic circuit communicably coupled to the PASS device, the safety logic circuit having at least an off state and an on state, the safety logic circuit comprising a timer configured to determine a time elapsed since the timer has been last reset, the safety logic circuit being configured to operate at least in a normal condition and a damage condition, the safety logic circuit configured to:
switch from the off state to the on state upon receiving an activation signal from the PASS device, wherein the activation signal is indicative of the switching of the PASS device from a PASS off state to a PASS on state;
reset the timer upon switching to the on state;
generate a trigger signal in response to the timer exceeding a time threshold in the damage condition, wherein the damage condition corresponds to a physical or a thermal damage of the PASS device; and
reset the timer upon receiving a reset signal from the PASS device before the timer exceeds the time threshold in the normal condition; and
an alarm circuit communicably coupled to the safety logic circuit, wherein the alarm circuit is configured to generate an alarm signal upon receiving the trigger signal from the safety logic circuit.