Browse Prior Art Database

Digital Display for the Blind

IP.com Disclosure Number: IPCOM000083449D
Original Publication Date: 1975-May-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 3 page(s) / 51K

Publishing Venue

IBM

Related People

Nassimbene, EG: AUTHOR [+2]

Abstract

Large electromechanical displays are inexpensive in fabrication and operating costs with this nitinol 55 actuator element.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 3

Digital Display for the Blind

Large electromechanical displays are inexpensive in fabrication and operating costs with this nitinol 55 actuator element.

Nitinol 55 is a metal alloy of nickel and titanium which has a storing characteristic. A nitinol actuator is made in a predetermined shape. Warming a deformed piece of this metal alloy to moderate temperatures, causes it to revert to its predetermined shape. Because the metal has reasonably high-electric resistance, it is easily warmed to the necessary transition temperature range by passing electric current through it. Alternatively, a laser is directed on the nitinol metal to heat it. Indirect heating by an adjacent nichrome heater element also is contemplated. Thus a displacement display is readily formed.

A simple displacement type display for use by the blind is shown in Fig. 1. A panel 10 is bored in a pattern appropriate to the display; here a braille cell pattern is intended and tactile sensing is contemplated. A light shutter type display is readily assembled in an arrangement wherein the actuators cover and uncover apertures in the panel. In this tactile display, the panel 10 is an electric current conductor.

Actuators 12 have small (1.27 millimeter diameter) balls 14 on one end which are arranged in apertures 16 of the panel 10. The actuators 12 are formed as shown at the left, with the ball 14 protruding a short distance (0.51 mm) above the panel 10. The other ends of the actuators 12 are electrically and mechanically fastened to the panel 10, as shown. Short flexible electric wires 18 are connected near the ends of the nitinol 55 actuators 12, so that electric current may traverse the deformed portions of the actuators.

Reset bars 20 are arranged to press the actuators 12 down in the initial position. Optionally, other nitinol elements are arranged to reset the actuator elements, if so desired. Each will remain in place until it is heated. Electric current sufficient to warm the actuators 12 is selectively applied.

When heated, the actuators straighten out pushing the braille boss or "dot" above the upper surface of the panel 10. The current need be applied only for a fraction of a second to cause the nitinol wire to react. The selected actuato...