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:
Jun. 05, 2001
Filed:
Jan. 06, 2000
Patricia L. Williams, Rochester, NY (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
A stepper motor includes the following. A rotatable hub. A first shaped memory alloy (abbreviated to SMA) rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in a predetermined direction, and which can be deformed to reverse the shape change to rotationally uncouple from the hub. A first return spring connected with the first SMA rotary-driver for deforming the first SMA rotary-driver, when no longer heated, to reverse the shape change of the first SMA rotary-driver and rotationally uncouple the first SMA rotary driver from the hub. A second SMA rotary-driver, which when heated undergoes a shape change to rotationally couple with the hub and rotate the hub in the predetermined direction, and which when can be deformed to reverse the shape change to rotationally uncouple from the hub. A second return spring connected with the second SMA rotary-driver for deforming the second SMA rotary-driver, when no longer heated, to reverse the shape change of the second SMA rotary-driver and rotationally uncouple the second SMA rotary-driver from the hub. A control device for heating the first and second SMA rotary-drivers in succession and only one at a time. Thus, the first and second SMA rotary-drivers can take turns to stepwise rotate the hub in the predetermined direction.