Method and apparatus for controlling a safety-critical process
AssigneePilz GmbH & Co. KG
InventorDietmar Seizinger
Life of this patent
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Abstract
The invention relates to a method and an apparatus for controlling safety-critical processes, such as the monitoring of protective doors, emergency stop switches, light curtains and the like. A control unit is connected to a plurality of I/O units via a data transmission link. The I/O units transmit process data to the control unit, with the process data being protected against transmission errors by means of a diversitary multiple transmission. The process data are encoded using a variable keyword in order to generate variably encoded process data. The variably encoded process data are transmitted to the control unit as part of the diversitary multiple transmission.
Claims20
A method for controlling a safety-critical process, comprising the steps of:
- providing a control unit for processing safety-critical process data,
- providing at least one I/O unit for remote signal input and output,
- providing a data transmission link for connecting the control unit and the at least one I/O unit,
- encoding the process data using a variable, constantly changing keyword in order to generate variably encoded process data including a defined dynamic behavior, and
- transmitting the variably encoded process data from the I/O unit to the control unit as a part of a redundant data transmission.
A method for controlling a safety-critical process, comprising the steps of:
- providing a control unit for processing safety-critical process data,
- providing an I/O unit connected to the control unit via a data transmission link, and
- transmitting the process data from the I/O unit to the control unit, with the process data being protected by means of a diversitary multiple transmission,
- wherein the process data are encoded at least once using a variable keyword in order to generate variably encoded process data, and wherein the variably encoded process data are transmitted to the control unit as part of the diversitary multiple transmission.
An apparatus for controlling a safety-critical process, comprising
- a control unit for processing safety-critical process data,
- at least one I/O unit for remote signal input and output, and
- a data transmission link for connecting the at least one I/O unit to the control unit,
- the at least one I/O unit being adapted to generate the process data from the signal input and comprising an encoder chip which is designed to encode the process data using a variable, constantly changing keyword in order to generate variably encoded process data resulting in a defined dynamic behavior, and
- the at least one I/O unit being designed to transmit the variably encoded process data to the control unit by means of a diversitary multiple data transmission via the data transmission link.
A control unit for processing safety-critical process data comprising:
- a portion for failsafe processing of the safety-critical process data,
- a keyword generator for generating a variable, constantly changing keyword, and
- a data link interface for receiving the safety-critical process data from a remote I/O unit, and for transmitting the keyword to the remote I/O unit, with the portion for failsafe processing being designed to read in and evaluate process data encoded using the variable, constantly changing keyword.
An I/O unit for remote signal input and output in an apparatus for controlling a safety-critical process, the I/O unit comprising a first interface for the remote signal input and output, and a second interface for transmitting process data relating to the signal input and output to a remote control unit, and comprising an encoder chip designed to encode the process data using a variable, constantly changing keyword in order to generate variably encoded process data having a defined dynamic behavior.
Dependencies are inferred from the claim text.