Hydraulic elevator having microprocessor-based, distributed control system

A hydraulic elevator having a distributed intelligence control system, said elevator comprising:

• a car having a door;
• a jack coupled to the car for raising and lowering the car between landings;
• a pump means for supplying hydraulic fluid to the jack;
• a valve means for controlling the flow of hydraulic fluid to and from the jack;
• means for registering floor calls for each of the landings;
• a power controller for selectively actuating said pump means and said valve means for up travel, and said valve means for down travel;
• door operator means mounted to said car including door drive means coupled to said door for opening and closing the door and including first microprocessor means for actuating said door drive means, said first microprocessor means including (a) means for executing an open door cycle, for opening the door in a predetermined, controlled speed pattern, responsive to an external open door command;
• and (b) means for executing a close door cycle, for closing the door in a predetermined, controlled speed pattern, responsive to an external door close command;
• a selector means for producing selector signals representative of car position and car travel and including second microprocessor means mounted to said car (a) for setting, responsive to an external run signal, target floor and target distance, (b) for storing a pre-selected slowdown distance for said target floor;
• (c) for calculating, responsive to selector signals, instantaneous target distance, and (d) for producing slowdown interrupt signals SDI representative of the car reaching the slowdown distance;
• and (e) for producing output signals representative of levelling position;
• a car logic controller ("CLC") mounted to said car comprising a third microprocessor means for controlling said power controller and for overseeing said door operator means and said selector means, said third microprocessor means including means for (a) issuing run commands to said power controller for selective actuation thereof;
• (b) issuing door open and door closed commands to said first microprocessor means;
• (c) issuing run signals to said second microprocessor means;
• (d) actuating, responsive to the receipt of slowdown interrupt signals SDI and floor call signals, said power controller to slow said car into a selected landing;
• and (e) actuating said power controller for levelling of said car, wherein said power controller includes means for levelling said car responsive to selector signals;
• and
• communication means among said first, second, and third microprocessor means for sending and receiving communications, wherein each microprocessor means has stand alone intelligence for performing certain of predefined control tasks independent of the other microprocessors.