Safety control system

• US 7,912,563 B2
• Filed: 07/21/2008
• Issued: 03/22/2011
• Est. Priority Date: 07/19/2007
• Status: Active Grant

• Current Assignee: Yokogawa Electric Corporation
• Original Assignee: Yokogawa Electric Corporation
• Inventors: Oosako, Satoru
• Primary Examiner(s): Patel; Ramesh B
• Application Number:
  US12/220,006
• Publication Number:
  US 20090228116A1
• Time in Patent Office: 974 Days
• Field of Search: 700/21, 700 79- 80, 340540-541, 702/114, 702/118, 702/184
• US Class Current: 700/79
• CPC Class Codes: G05B 19/4186 by protocol, e.g. MAP, TOP
• CPC Class Codes: G05B 2219/25218 Broadcast mode, originator, destinator address, command, check data
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A safety control system includes a plurality of safety control stations connected to a control bus to communicate with each other and with a distributed control system including a plurality of control stations connected to the control bus, wherein each of the plurality of safety control stations has an interface through which each of the plurality of safety control stations is connected to the control bus for transmitting own data of each of the plurality of safety control stations to all other safety control stations by broadcasting at a fixed cycle via the control bus and for receiving by each safety control station transmitted data from all other safety control stations, and wherein the interface implements a safety layer used to generate and diagnose safety information.

Claims

1. A safety control system, comprising:

a plurality of safety control stations connected to a control bus to communicate with each other and with a distributed control system including a plurality of control stations connected to said control bus,

wherein each of the plurality of safety control stations has an interface through which each of the plurality of safety control stations is connected to the control bus for transmitting own data of each of the plurality of safety control stations to all other safety control stations by broadcasting at a fixed cycle via the control bus and for receiving by each safety control station transmitted data from all other safety control stations, and

wherein said interface implements a safety layer used to generate and diagnose safety information.

2. A safety control system according to claim 1, wherein each of the plurality of safety control stations is configured to add the safety information to the own data and to transmit the own data together with the safety information to the control bus at the fixed cycle.

3. A safety control system according to claim 1, wherein the safety information contains a CRC code.

4. A safety control system according to claim 1, wherein each of the plurality of control stations and each of the plurality of safety control stations is configured to broadcast the same amount of bytes within the fixed cycle, the amount of bytes transmitted by each of the plurality of control stations being assigned to data, and the amount of bytes transmitted by each of the plurality of safety control stations being shared by data and by the safety information.

5. A safety control system according to claim 4, wherein the amount of bytes transmitted within the fixed cycle is 32 bytes, and the safety information has 16 bytes.

6. A method for safety control in a system including a plurality of safety control stations connected to a control bus to communicate with each other and with a distributed control system including a plurality of control stations connected to the control bus, said method comprising the steps of:

transmitting own data of each of the plurality of safety control stations to all other safety control stations by broadcasting at a fixed cycle through an interface by which each of the plurality of safety control stations is connected to the control bus;

receiving by each of the plurality of safety control stations transmitted data from all other safety control; and

generating and diagnosing safety information by a safety layer of said interface.

7. A safety control method according to claim 6, further comprising the steps of:

adding the safety information to the own data; and

transmitting the own data together with the safety information to the control bus at the fixed cycle.

8. A safety control method according to claim 6, wherein the safety information contains a CRC code.

9. A safety control method according to claim 6, wherein said transmitting by each of the plurality of control stations and each of the plurality of safety control stations broadcasts the same amount of bytes within the fixed cycle, the amount of bytes transmitted by each of the plurality of control stations being assigned to data, and the amount of bytes transmitted by each of the plurality of safety control stations being shared by data and by the safety information.

10. A safety control method according to claim 9, wherein the amount of bytes transmitted within the fixed cycle is 32 bytes, and the safety information has 16 bytes.