DAVID J ALTLAND
Engineers in Wellsville, PA
License number
Pennsylvania PE030398E
Category
Engineers
Type
Professional Engineer
Address
Address
Wellsville, PA 17365
Personal information
See more information about DAVID J ALTLAND at radaris.comName
Address
Phone
132 Mimosa Dr, York, PA 17402
1750 Topaz Rd, York, PA 17408
220 Briar Hill Rd, Lititz, PA 17543
2760 Potosi Rd, New Freedom, PA 17349
315 E Front St, Lewisberry, PA 17339
Professional information
See more information about DAVID J ALTLAND at trustoria.com
Explosion-Protected Computer Terminal
Explosion-Protected Computer Terminal
US Patent:
4847602, Jul 11, 1989
Filed:
Oct 18, 1985
Appl. No.:
6/789244
Inventors:
David J. Altland - Wellsville PA
Wojciech R. Wyczalkowski - Middletown PA
Wojciech R. Wyczalkowski - Middletown PA
Assignee:
HMW Enterprises, Inc. - Etters PA
International Classification:
G09G 100
US Classification:
340700
Abstract:
A computer terminal including a cathode ray tube display in an explosion-protected electrically grounded enclosure. The front wall of the enclosure is formed by a hermetically sealed keypanel having an electrically conductive window located opposite the display for discharging, without sparking, static electricity to the grounded enclosure. The keypanel is formed from a rigid metal plate containing a pattern of several apertures in which the mounted pressure-sensitive piezoelectric switches which serve as data key input devices. A deformable metal sheet covers the rigid metal plate and apertures and has defined therein pressure points opposite corresponding apertures. The rigidity of the metal plate is sufficient to prevent pressure applied to one pressure point from affecting a switch at any other pressure point.