Browse Prior Art Database

Making Magnetized Spheres having Contrastingly Colored Hemispheres

IP.com Disclosure Number: IPCOM000092898D
Original Publication Date: 1967-Mar-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

French, WK: AUTHOR

Abstract

Magnetic blackboards, employing tiny spheres free to rotate under the influence of a magnetized writing stylus to selectively expose the white hemispheres of the spheres to view to create the display, require many thousands of constrastingly colored magnetized balls. A method of fabricating these balls consists of the following succession of steps:

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Making Magnetized Spheres having Contrastingly Colored Hemispheres

Magnetic blackboards, employing tiny spheres free to rotate under the influence of a magnetized writing stylus to selectively expose the white hemispheres of the spheres to view to create the display, require many thousands of constrastingly colored magnetized balls. A method of fabricating these balls consists of the following succession of steps:

1. Laminating a black and a white sheet of weakly magnetized magnetic plastic or magnetic rubber into a unitary laminar structure with the axes of magnetization aligned with the thickness of the two sheets,

2. Slicing or dicing the laminated sheet into cubes,

3. Tumbling the diced cubes to form spheres,

4. Cleaning the tumbled spheres in a magnetic separator to remove the dust particles adhered to them,

5. Orienting the spheres in a magnetic field by utilizing the residual magnetism of the spheres, and

6. Applying a strong magnetizing force to the thus oriented spheres to saturate them.

1