System having reset action

• US 4,094,463 A
• Filed: 03/23/1977
• Issued: 06/13/1978
• Est. Priority Date: 03/23/1977
• Status: Expired due to Term

• Current Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Original Assignee: Honeywell Incorporated (Honeywell International Inc.)
• Inventors: Milewski, Sylvester
• Primary Examiner(s): Wayner, William E.
• Application Number:
  US05/780,636
• Time in Patent Office: 447 Days
• Field of Search: 318/609, 236/82, 236/87, 137/86
• US Class Current: 236/82
• CPC Class Codes: G05B 11/50 in which the output signal represents a continuous function of the deviation from the desired value, i.e. continuous controllers
• CPC Class Codes: Y10T 137/2452 With counter-counter balancing pressure feedback

Abstract

A system is disclosed for providing reset action in a controller, having an averaging circuit for supplying a pilot signal which is the average of an input signal and a feedback signal, a relay having an input connected to receive the pilot signal for providing an output signal which bears a predetermined relationship with the pilot signal, the output signal being connected in a feedback circuit to supply the feedback signal to the averaging circuit, and a capacity which is either connected to the feedback circuit to delay only the feedback signal or connected between the averaging circuit and the relay to delay both the output signal and the feedback signal. The input signal may be a controller output such as a control variable and the output signal may be used to control a control element such as a condition affecting the control variable.

Claims

1. A system for providing reset action comprising:

pressure dividing means having a first input adapted to receive an input signal, a second input connected to receive a feedback signal and an output providing a pilot signal which is a division of said input signal and said feedback signal;

output means having an input and an output;

connecting means connecting said output of said pressure divider means to said input of said output means and connecting said output of said output means to said second input of said pressure divider means; and

,

capacity means connected to said connecting means for delaying a change in said feedback signal upon an occurrence of a change in said input signal,

said output means producing an output signal having a predetermined relationship to said pilot signal.

2. The system of claim 1 wherein said connecting means comprises a first connector connecting said output of said pressure divider means to said input of said output means and a second connector connecting said output of said output means to said second input of said pressure divider means.

3. The system of claim 2 wherein said capacity means is connected to said first connector.

4. The system of claim 3 wherein said output means comprises a relay for changing said output signal in a manner to counterbalance a division of any changes in said input signal by said pressure divider means.

5. The system of claim 4 further comprising sensor means for producing said input signal in response to a condition.

6. The system of claim 2 wherein said capacity means is connected to said second connector.

7. The system of claim 6 wherein said output means comprises a relay for changing said output signal in a manner to counterbalance a division of any changes in said input signal by said pressure divider means.

8. The system of claim 7 further comprising sensor means for producing said input signal in response to a condition.

9. A system for providing reset action comprising:

averaging means having a first input for receiving an input signal, a second input connected to receive a feedback signal, and an output for providing a pilot signal which is an average of said input signal and said feedback signal;

output means having an input and an output;

first connecting means connecting said output of said averaging means to said input of said output means;

second connecting means connecting said output of said output means to said second input of said averaging means for supplying said feedback signal;

capacity means connected to said second connecting means for delaying a change in said feedback signal upon an occurrence of a change in said input signal;

said output means producing an output signal bearing a predetermined relationship to said pilot signal.

10. The system of claim 9 wherein said output means comprises a relay for changing said output signal in a 2 to 1 relationship with changes in said pilot signal.

11. The system of claim 10 further comprising sensor means for providing said input signal dependent upon a sensed condition.

12. The system of claim 11 wherein said sensor means comprises a thermostat.

13. The system of claim 9 wherein said averaging means comprises a first restriction connected between said first input and said output of said averaging means, and a second restriction connected between said second input and said output of said averaging means, wherein said first restriction and said second restriction are substantially equal.

14. The system of claim 10 wherein said output means comprises a relay for changing said output signal in a 2 to 1 relationship with changes in said pilot signal.

15. A system for providing reset action comprising:

averaging means having a first input for receiving an input signal, a second input connected to receive a feedback signal, and an output for providing a pilot signal which is an average of said input signal and said feedback signal;

output means having an input and an output;

first connecting means connecting said output of said averaging means to said input of said output means;

second connecting means connecting said output of said output means to said second input of said averaging means for supplying said feedback signal; and

,

capacity means connected to said first connecting means for delaying a change in said feedback signal and in said output signal upon an occurrence of a change in said input signal;

said output means producing an output signal having a predetermined relationship to said pilot signal.

16. The system of claim 15 wherein said output means comprises a relay for changing said output signal in a 2 to 1 relationship with changes in said pilot signal.

17. The system of claim 16 further comprising sensor means for providing said input signal dependent upon a sensed condition.

18. The system of claim 17 wherein said sensor means comprises a thermostat.

19. The system of claim 15 wherein said averaging means comprises a first restriction connected between said first input and said output of said averaging means, and a second restriction connected between said second input and said output of said averaging means, wherein said first restriction and said second restriction are substantially equal.

20. The system of claim 19 wherein said output means comprises a relay for changing said output signal in a 2 to 1 relationship with changes in said pilot signal.