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:
Feb. 25, 2003
Filed:
Mar. 05, 2001
Lawrence Jaffe, Agoura Hills, CA (US);
John Riddle, Camarillo, CA (US);
Richard Becker, Camarillo, CA (US);
Refrigerator Manufactures, Inc., Commerce, CA (US);
Abstract
An automatic sliding door system suited for use in walk-in freezer or refrigerator units includes exterior and interior sensor units for opening one or more sliding doors. Each sensor unit comprises both a motion sensor and a presence detector. The motion sensor detects motion towards the sliding door(s), and opens the door(s) as they are approached. The motion sensor keeps the door(s) open so long as the motion is present. The presence detector of each sensor unit detects a change in the ambient conditions directly underneath the doorway, and keeps the door(s) open when the ambient conditions change. A brushless DC servo motor is preferably employed to move a pulley and thereby synchronously open and close the door(s). Optical sensors are deployed above the door(s) at selected deceleration and stopping points for the doors. Other features include a push plate or pushbutton, a key lock, and a multi-tier alarm system.