Safety system

• US 20060072251A1
• Filed: 09/30/2004
• Published: 04/06/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: NCC Nano, LLC
• Original Assignee: Nano Gas Technologies, Inc.
• Inventors: McCool, Steven C., Ross, Rens
• Granted Patent: US 7,543,170 B2
• Time in Patent Office: Days
• US Class Current: 361/1
• CPC Class Codes: G05B 9/02 electric

Abstract

A system for monitoring and controlling the safety system of equipment, which is used to insure personnel safety and cause the system to “fail safe” in the event of computer or software failure, the failure of a critical piece of hardware, or the opening of any interlock indicating, for example, the unexpected entry of personnel into a dangerous area. Provides an integrated system of timed status monitoring hardware and software for use in a distributed-network computer-controlled environment. The hardware piece of this system includes a digital I/O computer add-on card, or other hardware supporting high-speed alternating state telemetry, and a custom circuit card. Such a circuit, when used within the overall control system can monitor the state of interlock switches and monitor the status of the computer control system(s). Such a safety circuit can then cause a shutdown appropriate to the failure detected. In addition, it has an ability to sense local hardware status information and immediately signal the computer of any potentially dangerous situation.

Claims

1. A safety circuit comprising:

a detector circuit operable for receiving a first signal from a computer indicative of a satisfactory operation of software running on the computer; and

a switching circuit operable for removing power from equipment in response to an interruption in receipt of the first signal by the detector circuit.

2. The safety circuit as recited in claim 1, wherein the first signal permits high-speed alternating state telemetry, and wherein the switching circuit removes power from the equipment when there is an interruption in the high-speed alternating state telemetry received by the detector circuit.

3. The safety circuit as recited in claim 1, wherein the software further comprises software code that operates the equipment.

4. The safety circuit as recited in claim 2, further comprising circuitry for re-applying the power to the equipment in response to a continuing of the high-speed alternating state telemetry received by the detector circuit after an interruption of the first signal.

5. The safety circuit as recited in claim 1, further comprising an interlock circuit for removing the power from the equipment in response to a second signal produced by the equipment.

6. A safety circuit comprising:

a detector circuit operable for detecting high-speed alternating state telemetry on a first input;

a first counter coupled to the detector circuit and operable for outputting a first signal in response to an interruption in the high-speed alternating state telemetry received by the detector circuit;

a relay circuit; and

a first switching circuit coupled to the first counter and operable for opening the relay circuit in response to the first signal.

7. The safety circuit as recited in claim 6, further comprising:

a second counter coupled to the detector circuit and the first counter and operable for resetting the first counter in response to a continuance of the high-speed alternating state telemetry after the interruption, wherein the resetting of the first counter results in a closing of the relay circuit via the first switching circuit.

8. The safety circuit as recited in claim 6, further comprising:

an interlock circuit operable for opening the relay circuit in response to removal of a fiber optic signal received by the interlock circuit.

9. A safety system operable for controlling application of power to equipment, comprising:

a first computer running first software operable for controlling first equipment;

a first safety circuit coupled to the first computer;

a second computer running second software operable for controlling second equipment;

a network coupling the first computer to the second computer;

software for communicating first network signals from the second computer over the network to the first computer that software running on the second computer is operating satisfactorily; and

software for signaling to the first safety circuit to remove power from the first equipment when there is an interruption in receipt of the first network signals by the first computer.

10. The safety system as recited in claim 9, further comprising:

a second safety circuit coupled to the second computer;

software for communicating second network signals from the first computer over the network to the second computer that software running on the first computer is operating satisfactorily; and

software for signaling to the second safety circuit to remove power from the second equipment when there is an interruption in receipt of the second network signals by the second computer.

11. The safety system as recited in claim 10, wherein the interruption in the receipt of the first network signals will occur when the second safety circuit performs a power down of the second equipment.