Browse Prior Art Database

Magnetically Keyed Air Cylinder

IP.com Disclosure Number: IPCOM000089675D
Original Publication Date: 1977-Dec-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Gates, GA: AUTHOR

Abstract

This is a magnetically keyed free piston air cylinder especially adapted for precisely handling and orienting parts, such as semiconductor integrated circuit chips.

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 75% of the total text.

Page 1 of 2

Magnetically Keyed Air Cylinder

This is a magnetically keyed free piston air cylinder especially adapted for precisely handling and orienting parts, such as semiconductor integrated circuit chips.

Part handlers, such as chip placement machines, use small piston-activated vacuum pencils. In such equipment the parts being positioned must be precisely located at all times to a accuracy of better than +/= .003 of a inch. In the past vacuum pickup pencils were kept from rotating around their own axis by a mechanical key with all the attendant problems of wear, free play and friction known to exist with such mechanical keys.

The magnetic unit shown in the figures avoids all of the problems associated with mechanical keys while assuring greater positional accuracy. The unit comprises a cylinder 10 of nonmagnetic material into which is fitted an air-driven piston 11 fitted with a through vacuum pencil 12 and a poled magnetic core 13. Vacuum pencil 12 is adapted to be able to pick up an integrated circuit chip 14. Surrounding body 10 is a poled magnetic keyway in the form of magnetic ring 15. Magnetic ring 15 is arranged to magnetically couple with the poled magnetic core fitted to the piston 11. The magnetic coupling of the ring to the piston prevents axial rotation of the piston rod within the cylinder. If the magnetic poles on either the plate or the ring were changed, the axial rotation would change to a new preset location. In every instance when the piston is driven...