Relay contact monitoring system

• US 5,277,244 A
• Filed: 10/20/1992
• Issued: 01/11/1994
• Est. Priority Date: 10/20/1992
• Status: Expired due to Term

• Current Assignee: Hunter Fan Company (Griffon Corporation)
• Original Assignee: Hunter Fan Company (Griffon Corporation)
• Inventors: Mehta, Vinay
• Primary Examiner(s): RIVELL, JOHN A
• Application Number:
  US07/963,691
• Time in Patent Office: 448 Days
• Field of Search: 165/2, 165/12, 165/24, 165/25, 165/27
• US Class Current: 165/265
• CPC Class Codes: F23N 2223/08 Microprocessor; Microcomputer
• CPC Class Codes: F23N 5/242 using electronic means
• CPC Class Codes: G05D 23/1909 whose output amplitude can only take two discrete values
• CPC Class Codes: H01H 2047/006 Detecting unwanted movement of contacts and applying pulses to coil for restoring to normal status

Abstract

A switching system for switching on and off heating and air conditioning units in an environmental control system. The switching system includes a thermostat and a relay conductively coupled to the thermostat. The relay has a contact, which is responsive to a change signal for changing its position. The system further includes a programmable monitor having predetermined positions stored in a memory. The monitor is conductively coupled to the contact and to the thermostat for continually determining the position of the contact, and for sending a change signal to the relay for switching the position of the contact, as needed, to be in conformance with a predetermined position stored in the memory.

Claims

1. An air temperature control system comprising:

a. a thermostat;

b. a relay conductively coupled to the thermostat, the relay having a contact;

c. a programmable monitor conductively coupled to the contact and to the thermostat for continually determining the position of the contact, and adjusting the position to be in conformance with a predetermined position stored in the monitor.

2. The air temperature control system of claim 1 wherein the thermostat is a microprocessor-controlled programmable thermostat.

3. The air temperature control system of claim 2 wherein the monitor has a memory containing predetermined positions for the contact.

4. The air temperature control system of claim 3 wherein the relay is a snap action pulse relay.

5. The air temperature control system of claim 4, further including an air conditioning unit and a heating unit, and wherein the contact makes a connection between the thermostat and one of the units.

6. A programmable thermostat for use in an environmental control system, the thermostat comprising:

a. a relay having a contact;

b. a microprocessor conductively coupled to the contact for continually determining the position of the contact, and adjusting the position to be in conformance with a predetermined position.

7. The thermostat of claim 6 wherein the thermostat is a microprocessor-controlled programmable thermostat.

8. The thermostat of claim 7 wherein the microprocessor has a memory containing predetermined positions for the contact.

9. The thermostat of claim 8 wherein the relay is a snap action pulse relay.

10. The thermostat of claim 9, wherein the environmental control system includes an air conditioning unit and a heating unit, and wherein the contact makes a connection between the thermostat and one of the units.

11. A switching system for switching on and off a heating unit and an air conditioning unit in an environmental control system, the switching system comprising:

a. a thermostat;

b. a relay conductively coupled to the thermostat, the relay having a contact, the relay responsive to a change signal for changing its position;

c. a programmable monitor having predetermined positions stored in a memory, the monitor conductively coupled to the contact and to the thermostat for continually determining the position of the contact, and for sending a change signal to the relay for switching the position of the contact to be in conformance with a predetermined position stored in the memory.

12. The switching system of claim 11 wherein the change signal is a voltage pulse.

13. The switching system of claim 12 wherein the relay is a snap action relay.

14. The switching system of claim 13 wherein the thermostat is a microprocessor-controlled programmable thermostat.

15. A method for switching on and off heating and air conditioning units in an environmental control system, the system having a microprocessor-controlled programmable thermostat, a snap action relay conductively coupled to the thermostat, the relay having a contact, the relay responsive to a voltage pulse for changing the contact'"'"'s position, and a programmable monitor conductively coupled to the contact and to the thermostat, the monitor having a memory, the method comprising the steps of:

a. storing predetermined contact positions in the memory;

b. continually determining the position of the contact;

c. comparing the position of the contact with the predetermined contact positions; and

d. correcting the position by sending a voltage pulse to the relay for switching the position of the contact to be in conformance with a predetermined position stored in the memory.