Can bus router for building automation systems

• US 20050288823A1
• Filed: 08/31/2005
• Published: 12/29/2005
• Est. Priority Date: 03/05/2003
• Status: Abandoned Application

• Current Assignee: Google Inc. (Alphabet Inc.)
• Original Assignee: Google Inc. (Alphabet Inc.)
• Inventors: Adamson, Hugh Patrick, Hesse, Scott, Nicolay, William, McDermid, John
• Application Number:
  US11/216,685
• Publication Number:
  US 20050288823A1
• Time in Patent Office: Days
• US Class Current: 700/276
• CPC Class Codes: G05B 15/02 electric

Abstract

Systems and methods for implementing CAN bus routers in building automation systems are disclosed. An exemplary system may comprise a control area network (CAN) backbone. At least one CAN router may be connected in-line to the CAN backbone. A plurality of automation devices may be connected to the at least one CAN router for communication over the CAN backbone.

Claims

1. An expandable building automation system comprising:

a control area network (CAN) backbone;

at least one CAN router connected in-line to the CAN backbone; and

a plurality of automation devices connected to the at least one CAN router for communication over the CAN backbone.

2. The building automation system of claim 1 wherein the at least one CAN router is a hub.

3. The building automation system of claim 1 wherein the at least one CAN router is a switch.

4. The building automation system of claim 1 wherein the at least one CAN router receives a CAN signal over the CAN backbone and automatically multicasts the CAN signal to at least one automation device connected to the CAN router.

5. The building automation system of claim 1 further comprising a plurality of CAN routers connected to one another in a daisy-chain configuration.

6. The building automation system of claim 5 wherein the daisy-chain configuration includes a first CAN router coupled directly to the CAN backbone, and at least one expansion CAN router coupled to the first CAN router.

7. The building automation system of claim 1 wherein at least one of the automation devices includes a remote transmitter connected to the CAN router.

8. The building automation system of claim 7 wherein at least one of the automation devices includes control device issuing signals to a controlled device via the remote transmitter.

9. The building automation system of claim 1 wherein the CAN backbone remains operable even if the at least one automation device is inoperable.

10. The building automation system of claim 1 further comprising at least one CAN processor in the CAN router directly coupled to the CAN backbone.

11. The building automation system of claim 10 further comprising at least one cascading processor in the CAN router, the cascading processor connected serially to the CAN processor.

12. The building automation system of claim 1 wherein the at least one CAN router provides electrical power to automation devices connected to the CAN router.

13. A method of configuring a building automation system, comprising:

providing a control area network (CAN) backbone for a building having a plurality of automation zones;

providing at least one CAN router for connecting a plurality of automation devices in each automation zone; and

communicatively coupling the plurality of automation devices to one another over the CAN backbone via the at least one CAN router.

14. The method of claim 13 further comprising connecting at least one CAN router to a primary CAN router in a daisy-chain configuration.

15. The method of claim 13 further comprising connecting at least one expansion CAN router to a primary CAN router in a daisy-chain configuration.

16. The method of claim 13 further comprising connecting a plurality of CAN routers to a primary CAN router.

17. The method of claim 13 further comprising communicatively coupling a wireless automation device with the CAN backbone via the at least one CAN router.

18. The method of claim 13 further comprising expanding capacity of the CAN backbone without a repeater, while maintaining full functionality of the CAN backbone.

19. A building automation system, comprising:

localized communication means for communicating control area network (CAN) signals for building automation; and

router means for connecting a plurality of automation devices to the localized communication means.

20. The building automation system of claim 19 wherein the router means is expandable in a daisy-chain configuration.

21. The building automation system of claim 19 further comprising means for maintaining integrity of the localized communication means even if the router means is inoperable.