03942077 is referenced by 37 patents and cites 7 patents.

By providing an input/output panel housing which is readily connectible to adjacent housings and which cooperates with up to four removable input/output modules, a completely expandable, modularized input/output panel construction is achieved. Each housing accommodates up to four "plug-in" input/output modules, and is constructed so that the wiring from the equipment being controlled is connected directly to fixed terminals and need not be removed when the input/output modules are removed or replaced. Since each housing is readily connectible to adjacent housings, the input/output panel board construction of this invention is completely flexible and readily expandable to meet any desired operational needs.

Title
Modular panel construction for programmable controller and frame therefore
Application Number
5/460037
Publication Number
3942077
Application Date
April 11, 1974
Publication Date
March 2, 1976
Inventor
Howard A Powers
Medfield
MA, US
Agent
Mattern Ware and Davis
Assignee
Modicon Corporation
MA, US
IPC
H02B 1/04
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