Slow opening and fast closing gas valves and related methods

Patent metadata

Field	Value
Publication number	US-10006664-B2
Application number	US-201514708994-A
Country	US
Kind code	B2
Filing date	May 11, 2015
Priority date	May 11, 2015
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

Disclosed are exemplary embodiments of apparatus and methods for slow-opening and fast-closing of a gas valve. In an exemplary embodiment, a gas valve generally includes an inlet, and at least one bi-directional metering orifice configured to discharge gas from the inlet in a first direction in the gas valve to provide a slow opening of the gas valve, and to discharge gas in a second direction in the gas valve to provide a fast closing of the gas valve.

First claim

What is claimed is:

1. A gas valve comprising:
an inlet; and
at least one bi-directional metering orifice configured in the gas valve to discharge gas from the inlet in a first direction in the gas valve through a single gas pathway configured with the at least one bi-directional metering orifice, to provide a slow opening of the gas valve for allowing a desired flow rate of the gas through the gas valve to prevent flame rollout or rough ignition when a combustion cycle is started, and to discharge gas in a second direction in the gas valve through the single gas pathway configured with the at least one bi-directional metering orifice, to provide a fast closing of the gas valve to shut off the flow of the gas through the gas valve within a desired closing time to prevent candling of a flame after the gas valve is closed,
wherein the at least one metering orifice is configured with a first discharge coefficient for providing the slow opening, and with a second discharge coefficient for providing the fast closing, and
wherein the at least one bi-directional metering orifice is configured for metering gas to fuel a gas-fueled appliance.

2. The gas valve of claim 1 , wherein the at least one metering orifice is configured to meter a gas flow rate into and out of a chamber defined by a regulating diaphragm of the gas valve, the diaphragm referencing atmospheric pressure outside the chamber.

3. The gas valve of claim 1 , wherein the at least one metering orifice is configured to meter a gas flow rate into and out of a chamber defined by a regulating diaphragm of the gas valve, the diaphragm referencing gas flow outside the chamber.

4. The gas valve of claim 1 , wherein the first discharge coefficient is about 0.60 and the second discharge coefficient is about 0.90.

5. The gas valve of claim 1 , wherein the at least one metering orifice is configured to meter a gas flow rate through a channel connecting the inlet with a gas-receiving chamber defined by a servo-regulator diaphragm, the first direction being toward the gas-receiving chamber, and the second direction being toward the inlet.

6. The gas valve of claim 1 , wherein the at least one metering orifice is configured to meter a gas flow rate into and out of a chamber defined by a regulating main diaphragm of the gas valve, the diaphragm referencing gas valve outlet pressure outside the chamber.

7. The gas valve of claim 1 , wherein each of the at least one metering orifice comprises a first through-hole edge against which gas flows in the first direction, and a second through-hole edge different from the first through-hole edge and against which gas flows in the second direction.

8. The gas valve of claim 7 , wherein the first through-hole edge comprises a sharp edge, and the second through-hole edge comprises one of the following: a chamfer lead, an inverted chamfer lead, an inverted fillet lead, a cone lead, and a radius lead.

9. The gas valve of claim 1 , wherein the at least one bi-directional metering orifice comprises a plurality of orifices positioned in series.

10. A gas-fueled appliance comprising the gas valve of claim 1 .

11. A method of controlling fluid flow through a gas valve, the method comprising:
directing gas from an inlet of the gas valve in a first direction through a bi-directional metering orifice in the gas valve through a single gas pathway with the bi-directional metering orifice, to slow an opening of the gas valve so as to allow a desired flow rate of the gas through the gas valve to prevent flame rollout or rough ignition when a combustion cycle is started; and
directing gas through the bi-directional metering orifice in a second direction opposite the first direction through the single gas pathway with the bi-directional metering orifice, to provide a fast closing of the gas valve so as to shut off the flow of the gas through the gas valve within a desired closing time to prevent candling of a flame after the gas valve is closed,
wherein directing the gas in the first direction comprises directing the gas past a first through-hole edge of the bi-directional metering orifice that provides a first flow rate through the bi-directional metering orifice, the first flow rate being slower than a second flow rate provided in the second direction by a second through-hole edge of the bi-directional metering orifice, and
wherein the bi-directional metering orifice is for metering gas to fuel a gas-fueled appliance.

12. The method of claim 11 , wherein the bi-directional metering orifice is configured with a first discharge coefficient of about 0.60 for gas directed in the first direction through the bi-directional metering orifice; and wherein the bi-directional metering orifice is configured with a second discharge coefficient of about 0.90 for gas directed in the second direction.

13. A gas valve comprising:
an inlet; and
at least one metering orifice in the gas valve and having a through-hole through which the orifice is configured to discharge gas from the inlet in a first direction in the gas valve through a single gas pathway configured with the at least one metering orifice, to provide a slow opening of the gas valve for allowing a desired flow rate of the gas through the gas valve to prevent flame rollout or rough ignition when a combustion cycle is started, and to discharge gas in a second direction opposite the first direction through the single gas pathway configured with the at least one metering orifice, to provide a fast closing of the gas valve to shut off the flow of the gas through the gas valve within a desired closing time to prevent candling of a flame after the gas valve is closed, wherein the at least one metering orifice is configured with a first discharge coefficient for providing the slow opening, and with a second discharge coefficient for providing the fast closing.

14. The gas valve of claim 13 , wherein the first discharge coefficient is about 0.60 and the second discharge coefficient is about 0.90.

15. The gas valve of claim 13 , wherein the through-hole extends between a sharp edge at a first face of one of the at least one orifice and one of the following at a second face of the one of the at least one orifice: a chamfer lead, an inverted chamfer lead, an inverted fillet lead, a cone lead, and a radius lead.

16. The gas valve of claim 13 , wherein the at least one metering orifice comprises a plurality of orifices positioned in series.

17. The gas valve of claim 13 , wherein the first discharge coefficient is about 0.60 and the second discharge coefficient is about 0.98.

18. A gas-fueled appliance comprising the gas valve of claim 13 .

19. The gas valve of claim 13 , wherein one of the at least one orifice comprises two edges having different shapes selected from the following: a sharp edge, a chamfer lead, an inverted chamfer lead, an inverted fillet lead, a cone lead, and a radius lead.

20. The gas valve of claim 13 , wherein the at least one metering orifice receives gas upstream of a main diaphragm so as to meter gas flow into and out of a chamber on one side of the main diaphragm.

Assignees

• Emerson Electric Co

Inventors

• Bronson John M

Classifications

• F24H9/2035 Primary

  using fluid fuel · CPC title

• F16K31/128

  servo actuated · CPC title

• G05D16/2093

  with combination of electric and non-electric auxiliary power · CPC title

• G05D16/2095

  using membranes within the main valve · CPC title