Object detectors

• US 2,826,753 A
• Filed: 04/13/1954
• Issued: 03/11/1958
• Est. Priority Date: 04/13/1954
• Status: Expired due to Term

• Current Assignee: Reynold S. Chapin
• Original Assignee: Reynold S. Chapin
• Inventors: Chapin, Reynold S.
• Application Number:
  US03/422,764
• Time in Patent Office: 1,428 Days
• US Class Current: 367/93
• CPC Class Codes: G01S 1/72 using ultrasonic, sonic or infrasonic waves
• CPC Class Codes: G01S 13/56 for presence detection presence detection using near field arrangements G01V3/00, e.g. G01V3/08, G01V3/12; burglar, theft or intruder alarms with electrical actuation G08B13/22 - G08B13/26
• CPC Class Codes: G08B 13/1627 using Doppler shift detection circuits
• CPC Class Codes: Y10S 367/909 Collision avoidance

Claims