Browse Prior Art Database

Multiple-Orifice Abrasive Blasting Head

IP.com Disclosure Number: IPCOM000101491D
Original Publication Date: 1990-Aug-01
Included in the Prior Art Database: 2005-Mar-16
Document File: 2 page(s) / 65K

Publishing Venue

IBM

Related People

Douthitt, BL: AUTHOR [+3]

Abstract

Disclosed is a multiple-orifice abrasive blasting head designed for removing cured epoxy coating from copper lands and holes of raw cards to allow solder coating and/or test probing.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 83% of the total text.

Multiple-Orifice Abrasive Blasting Head

       Disclosed is a multiple-orifice abrasive blasting head
designed for removing cured epoxy coating from copper lands and holes
of raw cards to allow solder coating and/or test probing.

      Fig. 1 shows a schematic section of the present embodiment. The
blasting head consists of sheet steel plenum 1, perforated steel
plate 2, perforated brass plate 3 and gasket 4, which are assembled
together with multiple bolts 5 around the perimeter, creating vacuum
chamber 6.  Steel plate 2 is perforated by 92 randomly located holes
7.  Brass plate 3 is perforated by 92 randomly located holes 8 which
coincide with holes 7.  Multiple plastic media feed tubes 9 run from
media supply hopper 10 through gasket 4 into the perimeter of vacuum
chamber 6.  Connected to plenum 1 is a source of high pressure air
11, which is timer-controlled to provide a blast of air into the
plenum against baffle 12. The card to be cleaned 13, together with a
mask 14 defining the areas to be cleaned, is placed over plate 3 atop
spacers 15 and located by tooling pins 16.

      In operation, a blast of high pressure air raises the pressure
in the plenum which, in escaping through holes 7 and 8, creates a
vacuum of 4" Hg in vacuum chamber 6.  This vacuum draws baking soda
from supply hopper 10 through feed tubes 9 into vacuum chamber 6
where it is mixed with the air escaping through holes 8 in plate 3,
thus producing a pneumatic scrubbing action agains...