US 4,744,218 AGranted

Power transmission

OwnerThomas L. Edwards, Yehia M. El-Ibiary +4inventors

InventorsThomas L. Edwards, Yehia M. El-Ibiary, Rajamouli Gunda, Richard S. Leemhuis, Fred H. Phillips, Melvin A. Rode

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Abstract

An electrohydraulic system includes a plurality of electrohydraulic devices individually controlled by microprocessor-based control electronics. The device controllers are connected in common by a bidirectional serial data bus to a master controller for coordinating operation of the various devices. Internal programming within the master controller establishes a repetitive time-sequence of windows for communications with the various device controllers for downloading control signals and parameters, and for uploading data indicative of system status and operation. The various device controllers include internal programming for operating the associated hydraulic devices as a function of control signals and parameters received from the master controller.

Claims18

Dependent claims

An electrohydraulic system with distributed control comprising

a plurality of electrohydraulic devices responsive to electronic control signals for performing hydraulic operations and control means for providing said control signals, said control means including a plurality of individual device control means each associated with and dedicated to directly controlling operation at an associated hydraulic device, master control means and means coupling said master control means to all of said device control means for coordinating operation of said device control means and said hydraulic devices controlled thereby,
said coupling means comprising a bus common to all of said master and device control means, all of said device control means being constructed for connection to said common bus for individual communication with said master control means,
said bus comprising a serial data bus, and each of master and device control means including means for transmitting and receiving data on said bus,
said master control means including means for establishing a repetitive time sequence of communication windows and means for communicating with each of said device control means in turn during an associated said window, each said device control means including means for communicating with said master control means only during an associated said window, and means for performing control operation at the associated said device other than during said associated window,
each said master and device control means including memory means, means for receiving both address and data information, and means for storing said data information at locations in said memory means indicated by said address information.

2 more elements

An electrohydraulic system with distributed control comprising

a plurality of electrohydraulic devices responsive to electronic control signals for performing hydraulic operations and control means for providing said control signals, said control means including a plurality of individual device control means each associated with and dedicated to directly controlling operation at an associated hydraulic device, master control means and means coupling said master control means to all of said device control means for coordinating operation of said device control means and said hydraulic devices controlled thereby,
said coupling means comprising a bus common to all of said master and device control means, all of said device control means being constructed for connection to said common bus for individual communication with said master control means,
said master control means including means for establishing a maximum load at one of said hydraulic devices, said device control means including a controller coupled to said one of said devices and responsive to maximum load signals from said master control means for limiting operation at said one of said devices to said maximum load.

Dependencies are inferred from the claim text.