OPEN TOP RANGE AND ASSOCIATED GAS DISTRIBUTION SYSTEM

Abstract

A gas range includes a plurality of open-top burners and a gas distribution system for controlling gas feed to the open-top burners. The gas distribution system includes a primary manifold and a plurality of secondary manifolds. Each secondary manifold is connected to feed gas to one or more of the open-top burners. Each secondary manifold is connected to receive gas from the primary manifold through a respective safety shut-off device such that gas feed from the primary manifold to each secondary manifold is controlled independently of gas feed from the primary manifold to any other secondary manifold. The primary manifold and each secondary manifold may be configured as modular assemblies.

Description

TECHNICAL FIELD

This application relates generally to open top gas ranges and, more specifically, to a gas distribution system for an open top gas range.

BACKGROUND

Commercial gas ranges typically include multiple open top burners individually actuated by low-cost, mechanical throttle valves. Burner ignition has historically been achieved through standing pilots, in which gas is continuously dispersed at the pilot source regardless of flame presence. The high volume, low-cost, and open top nature of this traditional set-up, along with commercial kitchen ventilation requirements, has generally obviated any widespread adoption of flame sensing technology, as currently required in range ovens and other styles of commercial and residential cooking equipment.

However, stricter regulations, both in US and abroad, along with growing customer preference for 100% monitoring of open source flames, has increased demand for a scalable, cost-effective solution. Several mechanisms are available for sensing flame and controlling gas flow, but adoption to the rigors and high-BTU output of commercial open top burner operation has not been readily accomplished.

Commercial gas ranges typically distribute fuel gas through rigid pipe conduit manifolds. Manifolds may be continuous pieces of straight or bent pipe or may consist of multiple sections of pipe joined with conventional pipe fittings. Other embodiments include square or rectangular tubing. The primary function is to distribute the incoming gas to various range appliances such as open-top burners, griddles, and ovens, among other items.

Gas is distributed from manifolds to open-top burner assemblies through low-cost throttle valves, typically brass with threaded pipe end connections. These simple and reliable designs are capable of high flow rates and demanding operating environments. Likewise, gas can be distributed to standing pilots directly from manifolds through bleed-type valves, also brass and configured with threaded pipe end connections.

For years, the cooking industry has adopted stricter requirements and increased customer preference for safety control on gas appliances, particularly in residential markets. This has driven innovations in all-in-one combination gas valves, or valves that are configured with thermo-electric safety shut-off devices inside, along with manual throttling control. The main advantage of this set-up is space savings and fewer assembly steps. In other embodiments, the combination valves also contain pilot bleed-off ports, eliminating the need for a standalone pilot valve mounted on the manifold. One disadvantage for these types of set-ups is cost. In some cases, the cost for the combination valve set-up can be more than ten times the cost of a low-cost throttle valve. While this trade-off may be desirable in certain applications, particularly for single-burner applications or locations expected to require little or no servicing, the added cost presents a dilemma for large multi-burner set-ups prone to heavy usage and corresponding servicing.

The combination valve set-up also compromises efficiencies gained when convenient pilot flash tubes are used on burner assemblies. The pilot flash tube allows one standing pilot to ignite two or more burner assemblies. When combination valves are used, thermo-electric power needs to either be split to two separate valves, or an additional pilot flame source needs to be created. An alternative to any of the stated set-ups is digital control and automatic ignition sources; however, these are not considered fully adapted to commercial open-top burner use, and they do not permit the benefit of analog, or un-plugged, operation. Also, a combination valve or safety device (commonly push-button) dedicated for each burner will require twice as many lighting procedures as a set-up that is adapted to a flash tube pilot system. For large open-top burner set-ups, sometimes ten or twelve per assembly, this represents a significant amount of time and effort, possibly routine depending on night-time shut-down procedures, simply for lighting pilots.

What is needed is a gas distribution system with simple safety shut-off devices incorporated such that cost and design efficiencies of existing gas control valves, burner assemblies, and flash tube designs can be preserved. The system should desirably fit within existing space envelopes, permit ready servicing from the front of the assembly, and/or allow gas-supply connections to continue to be made for non-“open-top” appliances (e.g., an oven or griddle). The inventive system disclosed herein meets these objectives and can be considered applicable to any front-manifold, flash tube system of conventional open-top burner ranges.

SUMMARY

In one aspect, a gas range includes a plurality of open-top burners and a gas distribution system for controlling gas feed to the open-top burners. The gas distribution system includes a primary manifold and a plurality of secondary manifolds. Each secondary manifold is connected to feed gas to one or more of the open-top burners. Each secondary manifold is connected to receive gas from the primary manifold through a respective safety shut-off device such that gas feed from the primary manifold to each secondary manifold is controlled independently of gas feed from the primary manifold to any other secondary manifold.

In another aspect, a gas range includes a gas distribution system including a primary manifold, first and second secondary manifolds, and first and second safety shut-off devices. The first secondary manifold is connected to receive gas from the primary manifold through the first safety shut-off device. The second secondary manifold is connected to receive gas from the primary manifold through the second safety shut-off device.

In a further aspect, a gas distribution system is provided for a gas range including multiple open-top burners. The gas distribution system includes a primary manifold, first and second secondary manifolds, and first and second safety shut-off devices. The first secondary manifold is connected to receive gas from the primary manifold through the first safety shut-off device. The second secondary manifold is connected to receive gas from the primary manifold through the second safety shut-off device.

The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a commercial gas range;

FIG. 2 is an exploded perspective view of a gas feed system of the range of FIG. 1;

FIG. 3 is an assembled perspective view of the gas feed system;

FIG. 4 is a top plan view of the gas feed system;

FIG. 5 is a partial front elevation of the range of FIG. 1;

FIGS. 6A-6C show front elevation views of alternative feed systems for different numbers of open-top burners.

DETAILED DESCRIPTION

With significant cost, operation, and manufacturing/servicing benefits, the subject design described below, with reference to one or more specific embodiments, introduces a more valuable method for monitoring open-top burners and their pilots.

Referring to FIG. 1, an exemplary open-top gas range 10 is shown. In the illustrated embodiment four burners 12 are provided atop a range housing that incorporates a gas oven accessible by a door 16, but variations are possible, such as two burner arrangements, six burner arrangements, eight burner arrangements etc. Each burner may typically be covered by a respective, removable cookware support grate 14, but only two grates are shown in FIG. 1.

FIG. 2-4 show a gas feed system 20 of the range (but with only two of the burners 12 instead of four depicted). In the exploded view of FIG. 2 the modular nature of the overall system 20 is best seen. In this regard, a primary manifold assembly 22 includes a primary manifold 24, here L-shaped with a gas inlet port 26 located at a rear portion of the manifold that extends toward a back of the oven. The primary manifold assembly 22 also includes a gas control valve 28 mounted along the front, lateral leg of the manifold for delivering fuel gas from an outlet port of the primary manifold to a component of the appliance other than the open-top burners, which in the case of the range 10 of FIG. 1 would be the oven. Mounting brackets 30 are welded or otherwise attached to the primary manifold 24 in order to secure the primary manifold to a frame of the range. Additional mounting brackets could be provided as needed. A feed valve 31 to the oven pilot is also shown.

A pair of safety shut-off devices 32 are also mounted to the front, lateral leg of the primary manifold 24 at spaced apart locations from each other, here on opposite sides of the location of the gas control valve 28, for delivering fuel gas from respective outlet ports of the primary manifold to respective secondary manifold assemblies 34 that connect to the safety shut-off devices. Each safety shut-off device 32 may, by way of example, be a push-button thermo-electric valve that utilizes a feedback voltage from a thermocouple 36 (e.g., see the dashed line connection in FIG. 4) to maintain the valve in an open condition when pilot flame is detected, and likewise the valve closes by default when pilot flame is not detected.

Each secondary manifold assembly 34 includes a secondary manifold 40 with an adapter 38 connected to an inlet port of the secondary manifold for making the connection to a safety shut-off device 32 of the primary manifold. A set of mounting brackets 42 and 44 are provided for supporting the secondary manifold on the frame of the range. A pair of open-top burner valves 46 (one for each of the burners 12) are mounted to respective outlet ports of the secondary manifold 40 enabling individual, manual burner control. A pilot valve 48 (e.g., bleed-type) connects to another outlet port of the secondary manifold 40 to feed gas to a pilot burner 50 of the gas burner assembly 52. The secondary manifold 40 may include an additional outlet port closed by a plug 54.

Each burner assembly 52 (only one being shown) includes a venturi casting, two burner heads 12, air intake shutters, and a flash tube 64 for delivering the pilot flame to each burner head. A pilot assembly 60 is located between the burners, where the pilot assembly includes the pilot burner 50, an optional pilot starter 62 (e.g., a piezo igniter activated by a push-button or rotary knob), the thermocouple 36 and a tee-pilot hood 66. In one implementation, the starter of each pilot assembly may be triggered by the same manual actuator.

In the illustrated embodiment, the secondary manifold assemblies 34 are substantially identical in size and shape. Both secondary manifolds 40 are substantially aligned along a common horizontal axis. However, separate gas control shut-off devices 32 provide the gas feed connection from the primary manifold to each secondary manifold. As shown, the primary and secondary manifolds may exhibit intentional shaping and bends in order to preserve linear relationships and to facilitate total system modularity.

In a method of assembly of the gas feed system, the primary manifold assembly 22 is first assembled with safety shut-off devices 32 (in this example, push-button thermoelectric valves) and one or more non-“open-top” burner devices (e.g., oven thermostat, tube fitting, plug). The secondary manifold assemblies 34 are assembled, each with two open-top burner valves 46, a pilot valve 48, a plug 54, and an adapter 38. The primary and secondary manifold assemblies are then mounted onto a range body using the attached mount brackets. The adapters 38 slide into compression tube fittings on the safety shut-off devices 32, enabling easy assembly by rotating the compression nut (e.g., 70) provided on each safety shut-off device 32. This method of assembly, while just one example, permits isolated servicing and replacement of individual secondary manifolds and safety shut-off devices without removing other manifolds (e.g., referring to FIG. 3, the left secondary manifold assembly 34 can be removed without removal of the right secondary manifold assembly 34, and vice versa). In other methods of assembly, the safety shut-off devices 32 could be first attached to the secondary manifold assemblies, then joined directly or by other tubing, rigid or flex or otherwise, to the primary manifold 24.

From an operational standpoint, each shut-off device 32 controls whether gas will flow from an outlet port of the primary manifold 24 into one associated secondary manifold 40. Thus, a given shut-off device 32 acts as a main control as to whether gas can flow to any of the pilot burner 50 or the two the two open-top burners 12 of a burner assembly 52 that is connected to the secondary manifold 40 fed by the shut-off device 32.

To start a given pilot burner 50, the push-button 32′ of the shut-off device is actuated from the front of the range 10 (see FIG. 5), which feeds gas into the secondary manifold 40 and through the pilot valve 48 to the pilot burner 50. The igniter 62 is actuated (e.g., using a rotary actuator 72 at the front of the range). When the pilot burner 50 starts, the voltage feeback from the thermocouple 36 maintains the shut-off device open. The same process can be used to start the pilot burner of any other burner assemblies connected to the primary manifold 24 through respective secondary manifold assemblies. If the pilot burner of a given burner assembly 52 becomes extinguished, the thermocouple voltage feedback ceases causing the shut-off device 32 feeding that burner assembly 52 to close. However, the shut-off devices 32 feeding other burner assemblies operate independently and may remain open.

Referring to FIG. 5, valve knobs 80 for the open-top burners are shown, along with the valve knob 82 for the oven feed valve. A front gas control panel 84 on the range body includes spaced apart cutouts/openings 86, and each opening 86 is shared by the pair of burner control valves and the safety shut-off device of a given secondary manifold assembly. Thus, a separate cutout is provided for each secondary manifold assembly.

FIGS. 6A-6C shows potential alternative gas feed systems 20, 20′ and 20″ with alternate lengths of primary manifolds and corresponding varying numbers of secondary manifolds, where system 20′ includes a single secondary manifold assembly (e.g., for a two-top burner arrangement), system 20 includes two secondary manifold assemblies as primarily described above and system 20″ includes three secondary manifold assemblies (e.g., for a six-top burner arrangement). For construction of commercial ranges, open-top burners and other appliances are commonly specified in section widths of 12 inches. The subject gas feed systems may be designed accordingly for a 12-inch range, 24 inch range and 36 inch range, but this is not a requirement. The spacing between any two adjacent secondary manifold assemblies is nearly equal in the system 20″ of FIG. 6C. In the system 20′ of FIG. 6B, the spacing between secondary manifold assemblies may be similar to that of FIG. 6C, but may also be intentionally maximized to permit installation of a non-“open-top” burner valve.

As used herein, the terminology “outlet port” of a manifold can be defined as a dedicated opening in the pipe or conduit, or by extension, through a tee or similar style fitting known in the art for conveniently splitting fluid flow, in which case each terminal of the tee or fitting(s) can be defined as an outlet port of the manifold.

It is to be clearly understood that the above description is intended by way of illustration and example only, is not intended to be taken by way of limitation, and that other changes and modifications are possible.

Claims

1. A gas range, comprising: a plurality of open-top burners;a gas distribution system for controlling gas feed to the open-top burners, the gas distribution system including: a primary manifold,a plurality of secondary manifolds, each secondary manifold connected to feed gas to one or more of the open-top burners, each secondary manifold connected to receive gas from the primary manifold through a respective safety shut-off device such that gas feed from the primary manifold to each secondary manifold is controlled independently of gas feed from the primary manifold to any other secondary manifold.

2. The range of claim 1, wherein: each secondary manifold has an inlet port and at least one outlet port, for each secondary manifold, the respective safety shut-off device couples an outlet port of the primary manifold to the inlet port of the secondary manifold.

3. The range of claim 1 wherein each secondary manifold is substantially aligned along a common axis.

4. The range of claim 3 wherein each secondary manifold is substantially identical in size and shape.

5. The range of claim 3 wherein a linear distance between any two adjacent secondary manifolds is substantially equal.

6. The range of claim 1 wherein each secondary manifold includes at least two burner control valves for feeding respective open-top burners.

7. The range of claim 6 wherein each secondary manifold includes at least one pilot control valve.

8. The range of claim 7 wherein each pilot control valve delivers gas to a respective pilot burner, for each pilot burner: a thermocouple is associated with the pilot burner, and the thermocouple controls an open/closed state of the safety shut-off device that feeds gas to the secondary manifold that feeds the pilot burner.

9. The range of claim 4 wherein a separate gas control valve is located on the primary manifold between a pair of adjacent secondary manifolds.

10. The range of claim 2 wherein at least one secondary manifold can be removed from the range independent of removal of any other secondary manifold.

11. The range of claim 10 wherein at least one safety shut-off device can be removed from the range independent of removal of any other safety shut-off device.

12. The range of claim 1, further comprising a gas control panel, wherein two open-top burner control valves and one safety shut-off device are located on a common secondary manifold and share one continuous cut-out in the gas control panel.

13. A gas range, comprising: a gas distribution system including a primary manifold, first and second secondary manifolds, and first and second safety shut-off devices, wherein: the first secondary manifold is connected to receive gas from the primary manifold through the first safety shut-off device, andthe second secondary manifold is connected to receive gas from the primary manifold through the second safety shut-off device.

14. The range of claim 13 wherein: the primary manifold has an inlet port and at least first and second outlet ports,the first secondary manifold has an inlet port and multiple outlet ports,the second secondary manifold has an inlet port and multiple outlet ports,the first safety shut-off device couples the first outlet port of the primary manifold to the inlet port of the first secondary manifold,the second safety shut-off device couples the second outlet port of the primary manifold to the inlet port of the second secondary manifold.

15. The range of claim 14 wherein the first secondary manifold includes a first pilot feed valve, and the second secondary manifold includes a second pilot feed valve.

16. The range of claim 15 wherein: the first pilot feed valve delivers gas to a first pilot burner, a first thermocouple is associated with the first pilot burner, and the first thermocouple controls an open/closed state of the first safety shut-off device;the second pilot feed valve delivers gas to a second pilot burner, a second thermocouple is associated with the second pilot burner, and the second thermocouple controls an open/closed state of the second safety shut-off device.

17. The range of claim 16 wherein: the first pilot burner is arranged for igniting a first pair burners via a first flash tube arrangement;the second pilot burner is arranged for igniting a second pair of burners via a second flash tube arrangement.

18. A gas distribution system for a gas range including multiple open-top burners, the gas distribution system comprising: a primary manifold, first and second secondary manifolds, and first and second safety shut-off devices, wherein: the first secondary manifold is connected to receive gas from the primary manifold through the first safety shut-off device, andthe second secondary manifold is connected to receive gas from the primary manifold through the second safety shut-off device.

19. The system of claim 18 wherein: the first secondary manifold includes a first pilot feed valve;the second secondary manifold includes a second pilot feed valve;the first pilot feed valve delivers gas to a first pilot burner, a first thermocouple is associated with the first pilot burner, and the first thermocouple controls an open/closed state of the first safety shut-off device;the second pilot feed valve delivers gas to a second pilot burner, a second thermocouple is associated with the second pilot burner, and the second thermocouple controls an open/closed state of the second safety shut-off device.