06172875 is referenced by 57 patents and cites 11 patents.

A system of interlocking modules for use with a programmable logic controller. The system utilizes a plurality of modules, e.g. input/output modules, that are mechanically interlinked to obviate the need for a rack or back plane. Each module includes a movable plug portion that selectively may be moved into engagement with a corresponding plug receptacle of the next adjacent module. The mechanical interlocking features and the plug portions are designed to permit insertion and removal of individual modules disposed between adjacent modules, without moving either of the adjacent modules.

Title
Programmable logic controller module assembly and locking system
Application Number
9/193650
Publication Number
6172875 (B2)
Application Date
November 17, 1998
Publication Date
January 9, 2001
Inventor
Paul J Grosskreuz
West Bend
WI, US
Kevin G Hughes
Whitefish Bay
WI, US
Joel C Clemente
Mequon
WI, US
Anthony G Gibart
New Berlin
WI, US
Dennis G Schneider
New Berlin
WI, US
Michael S Baran
Elm Grove
WI, US
Yasuyuki Nakanishi
Nagoya
US
Takao Suzuki
Anjyo
US
Agent
William R Walbrun
US
John J Horn
US
Robert A Van Someren
US
Assignee
Rockwell Technologies
CA, US
IPC
G06F 1/16
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