Premixed gas burner and method for manufacturing a premixed gas burner

Abstract

The present invention relates to a premixed gas burner, - a non-cylindrical burner deck unit having a support portion between a periphery and an operating burner deck area, and a cavity in which at least a part of the support portion is disposed. The support portion extends between a first cavity wall portion and a second cavity wall portion over a length corresponding to at least half of the expected thermal shrinkage of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature, and the cavity end wall portion is spaced apart from the support portion edge by a distance corresponding to at least half of the expected thermal expansion of the burner deck unit on the support portion surface when heating the burner deck unit from the ambient temperature to the maximum operating temperature.

Description

Technical Field

[0001] The present invention relates to a premixed gas burner and a method for manufacturing the premixed gas burner. Such a premixed gas burner is used, for example, in water heater appliances, such as for obtaining hot tap water or for heating buildings.

Background Art

[0002] In a premixed gas burner, fuel gas is mixed with air or oxygen or other oxidant gas to form a premixed gas. This premixing is carried out upstream of the working burner deck area of the premixed gas burner, and combustion of the premixed gas takes place in the adjacent working burner deck area. The fuel gas is, for example, natural gas, methane, ethane, propane, butane, etc., which are optionally partially mixed with hydrogen or any of these mixtures.

Summary of the Invention

[0003] The premixed gas burner according to the first aspect of the present invention includes a non-cylindrical burner deck unit. In such a burner deck unit, due to local temperature differences in particular, temperature differences occur over time, resulting in variations in thermal expansion and contraction. When the burner deck unit is fixedly attached to the burner, variations in material stress occur in the burner deck unit over time. This is known to lead to failures due to thermal fatigue. In order to reduce the risk of early failure due to thermal fatigue, it is known to attach the burner deck unit in a floating manner, such that it can move relative to the frame to which the burner deck unit is attached during use. Thereby, the material stress accumulated in the burner deck unit can be reduced. However, the problem with a burner deck unit attached in such a floating manner is that it may shift from the intended position during use. As a result, the premixed gas may leak from the edge, or the burner deck unit may become detached from the frame to which the premixed gas burner is attached. Furthermore, due to deformation of the burner deck unit, there may be an undesirable contact between the outer parts of the premixed gas burner, such as the ignition pin, ionization pin, sensor, etc., and the burner deck unit. This can lead to a malfunction of the premixed gas burner. These problems are most prominent in flat or shallow burner deck units, but are not limited to such burner deck units.

[0004] An object of the present invention is to provide a premixed gas burner in which at least one of these problems is at least reduced, and a method for manufacturing such a gas burner.

[0005] The object of the present invention is achieved by a premixed gas burner, which - is a non-cylindrical burner deck unit having a flame support portion, and the flame support portion - has an operating burner deck area having a gas discharge port, and during use adjacent to the operating burner deck area, after the premixed gas flows through the gas discharge port, it is combusted, and the burner deck unit - has a peripheral edge, and - a support portion existing between the operating burner deck area and a support portion edge formed by at least a part of the peripheral edge of the burner deck unit, having a thickness of the support portion, and extending on a support portion surface perpendicular to the thickness of the support portion, and a non-cylindrical burner deck unit having - a metal frame adapted to hold the non-cylindrical burner deck unit, and is provided with The premixed gas burner further has a cavity in which at least a part of the support portion of the burner deck unit is disposed. The cavity is - Through which at least a part of the support portion of the burner deck unit extends into the cavity, a cavity opening; - The inner wall of the cavity, - A cavity end wall portion facing the cavity opening; - A first cavity wall portion; - A second cavity wall portion arranged opposite to the first cavity wall portion; And an inner wall of the cavity having Comprises The first cavity wall portion and the second cavity wall portion extend parallel or non-perpendicularly to the support portion surface, and the cavity end wall portion extends between the first cavity wall portion and the second cavity wall portion; The first cavity wall portion is defined by the cavity boundary region of the metal frame; The distance between the first cavity wall portion and the second cavity wall portion is greater than the thickness of the support portion; When both the frame and the burner deck unit are at the ambient temperature, the support portion extends between the first cavity wall portion and the second cavity wall portion over a length corresponding to at least half of the expected thermal shrinkage of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature, and the cavity end wall portion is separated from the support portion edge by a distance that is at least half of the expected thermal expansion of the burner deck unit on the support portion surface when heating the burner deck unit from the ambient temperature to the maximum operating temperature. The premixed gas burner according to the first aspect of the present invention comprises a non-cylindrical burner deck unit and a metal frame. The non-cylindrical burner deck unit includes a flame support portion. The flame support portion includes an operating burner deck area. The operating burner deck area includes a gas outlet. During use of the premixed gas burner, the premixed gas burns adjacent to the operating burner deck area after passing through the gas outlet of the operating burner deck area. The operating burner deck area includes a plurality of gas outlets arranged in a normal pattern. This pattern can be formed by holes and / or slots through a metal plate, or openings between adjacent wires of a woven wire mesh. The operating burner deck area is part of the flame support portion through which the premixed gas flows for combustion during use. Optionally, outside the operating burner deck area, the flame support portion is closed (e.g., there are no holes, slots, etc., or no openings between adjacent wires of a woven wire mesh), or is composed of openings (e.g., holes, slots, etc., or openings between adjacent wires of a woven wire mesh). The burner deck unit further includes a periphery and a support portion. The support portion exists between the operating burner deck area and a support portion edge formed by at least a part of the periphery of the burner deck unit. The support portion has a thickness of the support portion and extends in a support portion plane perpendicular to the thickness of the support portion. The support portion may be, for example, integral with the flame support portion, i.e., formed by a part of the flame support portion. In that case, at least a part of the periphery of the burner deck unit may be formed by the periphery of the flame support portion, optionally the whole. Optionally, there are a plurality of support portions. Optionally, the support portion is at least partially formed by a rim connected to the flame support portion. In that case, at least a part of the peripheral portion of the burner deck unit may extend to the outer periphery of the rim.

[0006] The premixed gas burner according to the first aspect of the present invention further comprises a metal frame adapted to hold a non-cylindrical burner deck unit. The metal frame may be formed, for example, by one or more metal plates, for example at least one curved metal plate, or may be made, for example, from one or more cast and / or machined metal parts, optionally in combination with one or more metal plates. The metal frame optionally further comprises a mounting plate for mounting the premixed gas burner to an appliance such as a heating appliance, for example a building heating system or a water heater system.

[0007] The premixed gas burner according to the first aspect of the present invention further comprises a cavity in which at least a part of the support portion of the burner deck unit is disposed. The cavity comprises a cavity opening and a cavity inner wall. The cavity inner wall comprises a cavity end wall portion, a first cavity wall portion, and a second cavity wall portion. At least a part of the support portion of the burner deck unit extends into the cavity through the cavity opening. The cavity end wall portion is disposed opposite the cavity opening. The second cavity wall portion is disposed opposite the first cavity wall portion. The first cavity wall portion and the second cavity wall portion extend parallel or non-perpendicular to the support portion surface, and the cavity end wall portion extends between the first cavity wall portion and the second cavity wall portion. The first cavity wall portion is formed by the cavity boundary region of the metal frame.

[0008] In the premixed gas burner according to the first aspect of the present invention, the distance between the first cavity wall portion and the second cavity wall portion is greater than the thickness of the support portion. As a result, there is a clearance between at least a part of the support portion disposed in the cavity and at least one of the first cavity wall portion and the second cavity wall portion.

[0009] In the premixed gas burner according to the first aspect of the present invention, when both the frame and the burner deck unit are at the ambient temperature, the support portion extends between the first cavity wall portion and the second cavity wall portion over a length corresponding to at least half of the expected thermal shrinkage of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Further, when both the frame and the burner deck unit are at the ambient temperature, the cavity end wall portion is spaced apart from the support portion edge by a distance that is at least half of the expected thermal expansion of the burner deck unit on the support portion surface when heating the burner deck unit from the ambient temperature to the maximum operating temperature.

[0010] The ambient temperature is the temperature of the burner deck unit when the premixed gas burner is not in use. This is, for example, the expected temperature at the installation location where the premixed gas burner is arranged, for example, the average expected temperature, for example, 20 °C in the case of indoor installation. The maximum operating temperature is the maximum temperature of the burner deck unit during normal operation. For example, the typical maximum operating temperature when using natural gas as the fuel gas in the premixed gas is between 800 °C and 975 °C. In other configurations of the premixed gas burner, the typical maximum operating temperature of the burner deck is, for example, about 600 °C. The typical operating temperature of the frame when using natural gas as the fuel gas in the premixed gas is, for example, 400 °C to 450 °C. In other configurations of the premixed gas burner, the typical maximum operating temperature of the frame is, for example, about 200 °C to 400 °C. Generally, the length that the support portion extends into the cavity and enters between the first cavity wall portion and the second cavity wall portion is longer than the distance between the first cavity wall portion and the second cavity wall portion on the side of the cavity facing the operating burner deck area of the flame support portion. Optionally, the support portion extends within the cavity and between the first cavity wall portion and the second cavity wall portion over a length of at least 1 millimeter, optionally over a length of at least 2 millimeters, for example over a length ranging from 1 millimeter to 10 millimeters, optionally over a length ranging from 1 millimeter to 7 millimeters, for example over a length ranging from 1.5 millimeters to 5 millimeters. Optionally, the cavity end wall portion is spaced from the support portion edge at a distance of at least 1 millimeter, optionally over a length of at least 2 millimeters, for example ranging from 1 millimeter to 10 millimeters, optionally from 1 millimeter to 7 millimeters, for example ranging from 1.5 millimeters to 5 millimeters.

[0011] Optionally, in the premix burner according to the first aspect of the present invention, when the frame and the burner deck unit are both at ambient temperature, the support portion, when cooling the burner deck unit from the maximum operating temperature to the ambient temperature, extends within the cavity and between the first cavity wall portion and the second cavity wall portion over a length corresponding to at least half of the expected thermal shrinkage of the burner deck unit on the support portion surface, in a direction perpendicular to the outer periphery of the operating burner deck area at a position adjacent to the support portion (i.e., adjacent to the support portion or a part thereof extending into the cavity). Thereby, during use, cooling, and heating of the burner deck unit, the reliability of the metal frame that holds the burner deck unit in the intended position is further enhanced.

[0012] Optionally, in the premix burner according to the first aspect of the present invention, when the frame and the burner deck unit are both at ambient temperature, the support portion extends within the cavity and between the first cavity wall portion and the second cavity wall portion over a length of at least the expected thermal shrinkage of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. This further enhances the reliability of the metal frame that holds the burner deck unit in its intended position during use, cooling, and heating of the burner deck unit.

[0013] Optionally, in the premix burner according to the first aspect of the present invention, when both the frame and the burner deck unit are at the ambient temperature, the cavity end wall portion is spaced apart from the support portion edge by a distance corresponding to at least the expected thermal expansion of the burner deck unit on the support portion surface when heating the burner deck unit from the ambient temperature to the maximum operating temperature. This further improves the reliability of the metal frame that holds the burner deck unit in its intended position during use, cooling, and heating of the burner deck unit, and reduces the high material stress risk in the burner deck unit during use, cooling, and heating of the burner deck unit.

[0014] Optionally, in the premix burner according to the first aspect of the present invention, when both the frame and the burner deck unit are at the ambient temperature, the support portion extends in the cavity and between the first cavity wall portion and the second cavity wall portion in a direction perpendicular to the outer periphery of the operating burner deck area at a position adjacent to the support portion (i.e., adjacent to the support portion or a part of it extending into the cavity) over a length corresponding to at least the expected thermal contraction of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. This further enhances the reliability of the metal frame that holds the burner deck unit in its intended position during use, cooling, and heating of the burner deck unit.

[0015] Optionally, in the premix burner according to the first aspect of the present invention, when both the frame and the burner deck unit are at the ambient temperature, the support portion extends in the cavity and between the first cavity wall portion and the second cavity wall portion over a length obtained by adding the support portion thickness to a length corresponding to at least the expected thermal shrinkage of the burner deck unit on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Thereby, the reliability of the metal frame that holds the burner deck unit in the intended position during use, cooling, and heating of the burner deck unit is further enhanced.

[0016] Optionally, in the premix burner according to the first aspect of the present invention, when both the frame and the burner deck unit are at the ambient temperature, the support portion, when cooling the burner deck unit from the maximum operating temperature to the ambient temperature, extends in the cavity and between the first cavity wall portion and the second cavity wall portion in a direction perpendicular to the outer periphery of the operating burner deck area at a position adjacent to the support portion (i.e., adjacent to the support portion or a part thereof extending into the cavity) over a length obtained by adding the support portion thickness to a length corresponding to at least the expected thermal shrinkage of the burner deck unit on the support portion surface. Thereby, the reliability of the metal frame that holds the burner deck unit in the intended position during use, cooling, and heating of the burner deck unit is further enhanced.

[0017] Optionally, in the premix burner according to the first aspect of the present invention, the cavity is delimited by the metal frame on at least two sides of the cavity. For example, the first cavity wall portion and the end cavity wall portion are formed by the metal frame.

[0018] In the premix burner according to the first aspect of the present invention, the burner deck unit is supported within the cavity. The distance between the first cavity wall portion and the second cavity wall portion is greater than the support portion thickness (therefore, there is a clearance between at least a part of the support portion disposed within the cavity and at least one of the first cavity wall portion and the second cavity wall portion), so that when the burner deck unit undergoes thermal expansion or thermal contraction due to temperature changes in the burner deck unit that occur, for example, during startup, normal operation (including adjustment operation), and shutdown, the support portion of the burner deck unit can move relative to the metal frame. For example, it occurs during startup, normal operation (including adjustment operation), and shutdown. Due to the distance between the support portion edge and the cavity end wall portion, when the temperature of the burner deck unit rises, the burner deck unit can expand freely. Surprisingly, even when a clearance small enough to prevent undesirable leakage of the premix gas at points along the periphery of the burner deck unit is selected, it is found that in most cases, the support portion is not caught in the cavity and the movement of the support portion of the burner deck unit within the cavity is not hindered. Furthermore, the support portion that extends within the cavity and extends between the first cavity wall portion and the second cavity wall portion with a length according to the present invention prevents the burner deck unit from detaching from the metal frame that holds the burner deck unit. During the operation of the premix gas burner, especially during adjustment, a temperature difference may occur between the burner deck unit and the frame. For example, the burner deck unit may be heated or cooled faster than the frame. When the length of the support portion extending within the cavity between the first cavity wall portion and the second cavity wall portion extends over a length according to the first aspect of the present invention, it is found that the problem of the burner deck unit detaching from the frame is reduced and further this problem is completely prevented. In one embodiment, the inner wall of the cavity is further defined by a counter plate facing the cavity boundary region of the frame and a spacer disposed between the cavity interface surface of the frame and the counter plate. In this embodiment, the counter plate defines the second cavity wall portion, and the spacer defines the cavity end wall portion. Optionally, the counter plate is connected to the metal frame, for example, by welding (e.g., one or more spot welds), or by rivets and / or bolts. Alternatively, the counter plate is integral with the metal frame. Optionally, the spacer is connected to the metal frame, for example, by welding (e.g., one or more spot welds), or by one or more rivets and / or bolts. Alternatively, the spacer is integral with the metal frame. Optionally, the counter plate is connected to the spacer, and the spacer is sequentially connected to the metal frame. Optionally, the spacer is sandwiched between the metal frame and the counter plate. Optionally, both the counter plate and the spacer are integral with the metal frame. Optionally, the counter plate and / or the spacer are individual components in themselves but form part of the metal frame. Optionally, the counter plate and / or the spacer are made of metal, such as steel, stainless steel, or aluminum. Alternatively, the counter plate and / or the spacer are made of resin, such as fiber-reinforced resin. This embodiment provides a practical method for implementing the invention that enables relatively easy manufacturing.

[0019] In one embodiment, the flame support portion has an inner surface facing the working burner deck area, the premixed gas burner further has a gas distribution plate, and the gas distribution plate is disposed adjacent to and spaced from the inner surface of the flame support portion. In this embodiment, a part of the gas distribution plate defines the second cavity wall portion. The gas distribution plate evenly flows the premixed gas to the operating burner deck area of the burner deck unit. For good functioning, the gas distribution plate is arranged upstream of the burner deck unit as viewed from the flow direction of the premixed gas. Due to the upstream arrangement of this gas distribution plate, a part of the gas distribution plate can be used to define the second cavity wall portion or a part thereof. Thereby, the number of parts required for manufacturing the premixed gas burner can be reduced. Optionally, the inner cavity wall is defined by the gas distribution plate on at least two sides of the cavity. For example, the second cavity wall portion and the end cavity wall portion are formed by the gas distribution plate. Optionally, the cavity is defined by the metal frame on at least two sides of the cavity. For example, the first cavity wall portion and the end cavity wall portion are formed by the metal frame.

[0020] In one embodiment, the distance between the part of the support portion present in the cavity and the first cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.2 mm to 1.0 mm, for example 0.4 mm, and / or the distance between the part of the support portion present in the cavity and the second cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.2 mm to 1.0 mm, for example 0.4 mm. Optionally, the thickness of the support portion is 0.6 mm to 1.2 mm, the distance between the part of the support portion present in the cavity and the first cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.2 mm to 1.0 mm, for example 0.4 mm, and / or the distance between the part of the support portion present in the cavity and the second cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.2 mm to 1.0 mm, for example 0.4 mm. Optionally, the average distance between the first cavity wall portion and the second cavity wall portion is 1.0 mm to 3.0 mm, for example 1.0 mm to 2.0 mm, optionally 1.0 mm to 1.2 mm. Optionally, the thickness of the support part is 0.4 mm to 1.2 mm, for example 0.6 mm to 1.2 mm, and the average distance between the first cavity wall part and the second cavity wall part is 1.0 mm to 3.0 mm, for example 1.0 mm to 2.0 mm, and optionally 1.0 mm to 1.2 mm. Optionally, the distance between the first cavity wall part and the second cavity wall part is between 1.2 times and 1.6 times the thickness of the support part. Optionally, the thickness of the support part is 0.4 mm to 1.2 mm, for example 0.6 mm to 1.2 mm, and the distance between the first cavity wall part and the second cavity wall part is 1.2 times to 1.6 times the thickness of the support part. Optionally, the thickness of the support part is 1.2 mm to 2.0 mm, and the distance between the first cavity wall part and the second cavity wall part is 1.1 times to 2.0 times the thickness of the support part, for example 1.1 times to 1.5 times the thickness of the support part, and optionally 1.1 times to 1.4 times the thickness of the support part. The average distance between the first cavity wall part and the second cavity wall part refers to the average distance between the first cavity wall part and the second cavity wall part across the length and / or width of the cavity. For example, when the first cavity wall part and the second cavity wall part are parallel to each other, the distance between the first cavity wall part and the second cavity wall part is the same at any position within the cavity. However, when the first cavity wall part and the second cavity wall part are not parallel to each other, for example, to provide a relatively large cavity opening for facilitating the entry of the support part, or to reduce the material stress in the support part at the position of the support part in the cavity opening, and they extend at an angle of, for example, 5° to 30° to each other, the distance between the first cavity wall part and the second cavity wall part may vary across the length and / or width of the cavity. In this embodiment, the cavity is relatively narrow. The advantage of this embodiment is that the risk of premixed gas leaking along the periphery and / or the support area of the burner deck unit is reduced. Surprisingly, it has been found that the narrow cavity does not, or hardly affects, the ability of the support part to move within the cavity to allow for thermal expansion or contraction of the burner deck unit. The same applies when the support part has, for example, an end part of a woven wire mesh.

[0021] In one embodiment, the flame support is a woven wire mesh or includes the woven wire mesh. The woven wire mesh includes a plurality of metal mesh wires, and the gas outlet is formed by adjacent groups of metal mesh wires. For example, the woven wire mesh has or consists of metal warp and weft threads, and these warp and weft threads optionally extend perpendicular to each other. Optionally, the flame support and / or the operating burner deck area has at least one straight edge, the vertical wires extend perpendicular to this straight edge, and the horizontal wires extend parallel to this straight edge. Alternatively, the flame support and / or the operating burner deck area has at least one straight edge, the horizontal wires extend perpendicular to this straight edge, and the vertical wires extend parallel to this straight edge. Alternatively, the flame support and / or the operating burner deck area has at least one straight portion, and both the weft and warp threads extend at an angle to this straight edge. Optionally, both the weft and warp threads extend at an angle of 45° to this straight portion. Woven wire mesh is known as a material for the flame support of premixed gas burners. However, when cutting a woven wire mesh for a flame support from a bulk woven wire mesh, sharp edges and / or burrs may be formed at the locations where the wires (e.g., vertical and / or horizontal wires) are cut. Such sharp edges and burrs can, especially when the support is formed of woven wire mesh, impede the ability of the support to move within the cavity under the influence of thermal expansion or contraction. Surprisingly, however, it has been found that this does not occur or occurs only rarely in the premixed gas burner according to the first aspect of the present invention. If you want to further reduce the risk of the support part getting caught in the cavity during the use of the premixed gas burner, the support part or each support part may be formed by a rim connected to the flame support part. Alternatively, or in addition thereto, especially when that part of the woven wire mesh forms part of the support part, at least a part of the edge of the woven wire mesh may be folded back onto the woven wire mesh.

[0022] In one embodiment, the flame support part is a metal plate or includes the metal plate, the metal plate has a plurality of holes, and the gas discharge port is formed by the holes in the metal plate. The holes penetrate the metal plate in the plate thickness direction. The holes can be, for example, circular or slot-shaped. The perforated metal plate is known as a material for the flame support part of the premixed gas burner. Tests have shown that the perforated metal plate is compatible with the design of the premixed gas burner according to the first aspect of the present invention. Furthermore, the perforated metal plate can be easily manufactured to have any desired outer peripheral contour, such as by laser cutting. The holes are formed, for example, by laser cutting or punching. Due to the flexibility of the outer peripheral shape, it is possible to easily manufacture a support part or a group of support parts integral with the flame support part. The metal plate is made of, for example, stainless steel or aluminum.

[0023] In one embodiment, at least a part of the flame support part extends in a plane or a curved surface. For example, the operating burner deck area extends in a plane or a curved surface. Optionally, the flame support part and / or the operating burner deck area is circular, elliptical, rectangular, square, hexagonal, or octagonal. Optionally, when the entire flame support part extends in a curved surface, the height of the flame support part is 50% or less of the width and / or length, or diameter of the flame support part. Optionally, the height of the flame support part is 30% or less of the width and / or length, or diameter of the flame support part. Optionally, when a part of the flame support extends in a curved surface shape, the height of the curved surface part of the flame support shall be 50% or less of the width and / or length, or diameter of the curved surface part of the flame support. Optionally, the height of the flame support shall be 30% or less of the width and / or length, or diameter of the curved surface part of the flame support. Optionally, when the operating burner deck area extends in a curved surface, the height of the operating burner deck area shall be 50% or less of the width and / or length, or diameter of the operating burner deck area. Optionally, the height of the operating burner deck area shall be 30% or less of the width and / or length, or diameter of the operating burner deck area. For example, the premix burner according to the first aspect of the present invention includes a planar or shallow burner deck unit having a flame support that extends partly or entirely in a planar or curved surface. Optionally, in the present embodiment, the metal frame further includes a mounting surface for mounting the premix gas burner to the appliance, and the mounting surface extends in a mounting plane. Optionally, at least one edge of the flame support and / or the operating burner deck area extends at an angle of 0° to 45° (including both 0° and 45°), optionally at an angle of 0° to 30° (including both 0° and 30°) with respect to the mounting plane. In practice, in this type of premix gas burner, the problem that the burner deck unit moves from the intended position during use seems to be the most prominent (although it can also occur in other shaped burner deck units). Therefore, in this type of premix gas burner, this invention seems to be particularly beneficial.

[0024] In one embodiment, the frame further includes a mounting plate for installing the premix gas burner to the heating appliance. Optionally, the mounting plate forms a mounting surface that extends in a mounting plane. Optionally, at least one edge of the flame support part and / or at least one edge of the working burner deck area extend at an angle of 0° to 45° (including both 0° and 30°) with respect to the mounting plate, and optionally extend at an angle of 0° to 30° (including both 0° and 30°) with respect to the mounting plate.

[0025] In one embodiment, the first cavity wall part and / or the second cavity wall part extend parallel to the support part surface or at an angle of 30° or less. In this embodiment, a relatively wide cavity opening is provided at the position of the support part in the cavity opening to enable easy access to the support part or to reduce the material stress in the support part.

[0026] In one embodiment, the support part is formed by the flame support part or by a rim connected to the flame support part. The rim is optionally formed from a metal plate connected to the flame support part. Optionally, the metal plate is bent and the edge of the flame support part is disposed between two portions of the overlapping metal plates to be fixed, for example, by a clamp. Optionally, when the support part is formed by the flame support part. Optionally, when the support part is formed by the flame support part, the support part consists of a single layer of the material of the flame support part. Alternatively, the support part is at least partially formed by a double layer of the material of the flame support part, for example, formed by folding back the material of the flame support part onto itself at the position of the support part. This embodiment provides a practical method for implementing the present invention.

[0027] The present invention further relates to a water heater comprising the premixed gas burner according to any one of the preceding claims. This water heater constitutes, for example, a part of a heating appliance, a building heating appliance and / or a water heater.

[0028] The first aspect of the present invention further relates to a method for manufacturing a premix burner according to the first aspect of the present invention. In a first variant of the method according to the first aspect of the present invention, the present invention comprises the following steps. - A step of bending a metal plate along a main fold line, the metal plate having a thickness, the first side of the metal plate being provided with at least two tabs, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding twice the thickness of the support portion to the thickness of the plate, the tab top being further away from the main fold line than the tab base, and the primary portion of the metal plate being angled with respect to the secondary portion of the metal plate, the primary portion being disposed on the first side of the main fold line, the secondary portion being disposed on the second side of the main fold line, the first side and the second side being opposite to each other, and the secondary portion having the tabs. - A step of disposing at least a part of the support portion of the burner deck unit adjacent to and / or on the primary portion of the metal plate. - A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tabs extending over at least a part of the support portion of the burner deck unit, the tabs being angled with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby the primary portion of the metal plate defining one of the first cavity wall portion or the second cavity wall portion, the tabs defining the other of the first cavity wall portion or the second cavity wall portion, and a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line defining the cavity end wall portion together form at least a part of the cavity inner wall of the cavity of the premix burner according to the first aspect of the present invention. Optionally, the steps of the method are performed in the order listed above.

[0029] A second variant of the method according to the first aspect of the present invention comprises the following steps. - A step of bending a metal plate along a main fold line, wherein the metal plate has a plate thickness, and at least two tabs are provided on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding twice the plate thickness to the thickness of the support portion, the tab top being further away from the main fold line than the tab base, and the primary portion of the metal plate being angled with respect to the secondary portion of the metal plate, the primary portion being disposed on a first side of the main fold line, the secondary portion being disposed on a second side of the main fold line, the first side and the second side facing each other, and the secondary portion having the tab, - A step of disposing at least a part of the support portion of the burner deck unit adjacent to and / or on the primary portion of the metal plate, - A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tab extending parallel to but not overlapping at least a part of the support portion of the burner deck unit, the tab being angled with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby at least a part of the inner wall of the cavity of the premix burner according to the first aspect of the present invention is formed by the primary portion of the metal plate defining the first cavity wall portion or the second cavity wall portion and a portion of the secondary portion of the metal plate defining the cavity end wall portion located between the main fold line and the secondary fold line. Optionally, the steps of the method are performed in the order listed above.

[0030] A third variant of the method according to the first aspect of the present invention comprises the following steps. - A step of bending a metal plate along a main fold line, wherein the metal plate has a plate thickness, and at least two tabs are provided on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding twice the plate thickness to the thickness of the support portion, the tab top being further away from the main fold line than the tab base, and the primary portion of the metal plate being disposed at an angle with respect to the secondary portion of the metal plate, such that the primary portion is disposed on a first side of the main fold line, the secondary portion is disposed on a second side of the main fold line, the first side and the second side face each other, and the secondary portion has the tabs. - A step of disposing at least a part of the support portion of the burner deck unit adjacent to and / or on the tabs of the metal plate, such that it does not extend beyond the base of the tabs. - A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tabs extending over at least a part of the support portion of the burner deck unit, the tabs being disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby at least a part of the inner wall of the cavity of the premix burner according to the first side of the present invention is formed between the tab of the metal plate defining the first cavity wall portion or the second cavity wall portion and a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line and defining the cavity end wall portion, together with the primary portion of the metal plate and the tabs of the metal plate. Optionally, the steps of the method are performed in the order listed above.

[0031] The three variants of the method according to the first aspect of the present invention differ in the relative position of the tab and the primary part of the metal plate after performing the steps of the method, and in the arrangement position of the support part with respect to the metal plate in the method. Thus, each of the three variants of the method can manufacture different embodiments of the premixed gas burner according to the first aspect of the present invention.

[0032] The three variants of the method according to the first aspect of the present invention provide a reliable method for installing the premixed gas burner element of the burner deck unit by providing a clearance in the cavity. This clearance exists between the support part of the burner deck unit of the premixed gas burner according to the present invention and the first and / or second cavity wall parts. Since the tab base is located at a distance greater than the sum of twice the plate thickness from the main fold line and the thickness of the support part, sufficient space is ensured to provide a clearance in the cavity and accommodate the support part. By providing a tab on the metal plate to be bent, the position of the second fold line is accurately defined, and the height of the cavity, that is, the distance between the first cavity wall part and the second cavity wall part, is accurately defined. The predetermined stroke length of the punch also contributes to accurately obtaining the height of the cavity. In known manufacturing methods of premixed gas burners, a force-limited punch is used to install premixed burner elements such as flame support parts in the cavity. Instead, by using a punch with a predetermined stroke length, since the end point of the punch stroke is known in advance, the movement of the punch stops at the correct position, and the desired cavity height can be realized. As described above, when using the method according to the first aspect of the present invention, in any of its variants, when the tab is bent on the secondary fold line, no or almost no dimples are formed. Thereby, the cavity in which the support part or group of support parts of the burner deck unit is arranged is accurately formed. Thereby, the risk of premixed gas leaking through the cavity is reduced.

[0033] In one embodiment, the main folding line and / or the secondary folding line is a straight line. Alternatively, the main folding line and / or the secondary folding line is a straight line.

[0034] In one embodiment, after this folding, the metal plate is folded along the main folding line such that the angle between the primary portion of the metal plate and the secondary portion of the metal plate is between 80° and 100°, optionally 90°.

[0035] In one embodiment, after this folding, the secondary portion of the metal plate is folded along the secondary folding line such that the angle between the tab and the portion of the secondary portion of the metal plate located between the main folding line and the secondary folding line is between 80° and 100°, optionally 90°. As a result, the tab and / or the primary portion of the metal plate will extend over at least a part of the support portion of the burner deck unit.

[0036] In one embodiment, the metal plate is folded along the main folding line, the secondary portion of the metal plate is folded along the secondary folding line, and after this folding, the tab and the primary portion of the metal plate extend parallel to each other or at an angle of 30° or less.

[0037] The second aspect of the present invention relates to a method for manufacturing a premix burner. In a first modification of the method according to the second aspect of the present invention, the method comprises the following steps. - A step of folding a metal plate along a main folding line, wherein the metal plate has a plate thickness and is provided with at least two tabs on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being arranged at a distance from the main folding line, the distance being greater than twice the thickness of the premix gas burner element supported by the metal plate plus the thickness of the metal plate, and the tab top being further away from the main folding line than the tab base. The primary portion of the metal plate is disposed on a first side of the main fold line and the secondary portion of the metal plate is disposed on a second side of the main fold line by a fold line forming the primary portion of the metal plate disposed at an angle with respect to the secondary portion of the metal plate, the first side and the second side face each other, and the secondary portion has the step of having the tab. - Disposing at least a part of the support portion of the burner deck unit adjacent to and / or on the primary portion of the metal plate. - Bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tab extending over at least a part of the premix gas burner element of the burner deck unit, the tab being disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby the primary portion of the metal plate defining one of the first cavity wall portion or the second cavity wall portion, the tab defining the other of the first cavity wall portion or the second cavity wall portion, and a portion of the secondary portion of the metal plate defining the cavity end wall portion located between the main fold line and the secondary fold line together form at least a part of the inner wall of a cavity of a premix burner in which the premix gas burner element is disposed. Optionally, the steps of the method are performed in the order listed above.

[0038] In a second variant of the method according to a second aspect of the invention, the method comprises the following steps. - A step of bending a metal plate along a main fold line, wherein the metal plate has a plate thickness, and at least two tabs are provided on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding the thickness of a premixed gas burner element supported by the metal plate to twice the plate thickness, the tab top being further away from the main fold line than the tab base, and the primary portion of the metal plate being disposed at an angle with respect to a secondary portion of the metal plate, the primary portion being formed by a fold line and being disposed on a first side of the main fold line, the secondary portion being disposed on a second side of the main fold line, the first side and the second side facing each other, and the secondary portion having the tab, - A step of disposing at least a part of the premixed gas burner element of the burner deck unit adjacent to and / or on the primary portion of the metal plate, - A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tab extending parallel to but not overlapping at least a part of the premixed gas burner element of the burner deck unit, the tab being disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby at least a part of an inner wall of a cavity of the premixed burner in which the premixed gas burner element is disposed is formed by the primary portion of the metal plate defining the first cavity wall or the second cavity wall and a portion of the secondary portion of the metal plate defining the cavity end wall and located between the main fold line and the secondary fold line. Optionally, the steps of the method are performed in the order listed above.

[0039] In a third variant of the method according to a second aspect of the present invention, the method comprises the following steps. - A step of bending a metal plate along a main fold line, wherein the metal plate has a plate thickness, and at least two tabs are provided on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding a thickness of a premixed gas burner element supported by the metal plate to twice the plate thickness, the tab top being further away from the main fold line than the tab base, and the primary portion of the metal plate being angled with respect to a secondary portion of the metal plate, such that the primary portion is disposed on a first side of the main fold line, the secondary portion is disposed on a second side of the main fold line, the first side and the second side face each other, and the secondary portion has the tabs. - A step of disposing at least a part of the premixed gas burner element of the burner deck unit adjacent to and / or on the tabs of the metal plate so as not to extend beyond the base of the tabs. - A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, the secondary fold line being disposed on the tab base, the tabs extending over at least a part of the premixed gas burner element of the burner deck unit, the tabs being angled with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby the tabs of the metal plate defining the first cavity wall or the second cavity wall, together with a portion of the secondary portion of the metal plate defining the cavity end wall and located between the main fold line and the secondary fold line, form at least a part of the inner wall of the cavity of the premixed burner in which the premixed gas burner element is disposed between the primary portion of the metal plate and the tabs of the metal plate. Optionally, the steps of the method are performed in the order listed above.

[0040] In all three methods according to the second aspect of the present invention, the cavity formed by the method comprises a cavity opening and a cavity inner wall. The cavity inner wall comprises a cavity end wall portion, a first cavity wall portion, and a second cavity wall portion. At least a part of the support portion of the burner deck unit extends into the cavity through the cavity opening. The cavity end wall portion is disposed opposite to the cavity opening. The second cavity wall portion is disposed opposite to the first cavity wall portion. The first cavity wall portion and the second cavity wall portion extend parallel or non-perpendicularly to the support portion surface, and the cavity end wall portion extends between the first cavity wall portion and the second cavity wall portion.

[0041] The three variations of the method according to the second aspect of the present invention differ from each other in the relative position of the tab and the primary portion of the metal plate after performing the steps of the method, and in the position where the premixed gas burner element is disposed with respect to the metal plate in the method. Thereby, the three variations of the method each enable the manufacture of different embodiments of the premixed gas burner according to the second aspect of the present invention.

[0042] The three variations of the method according to the second aspect of the present invention provide a reliable method of providing a clearance in the cavity for mounting the premixed gas burner element of the burner deck unit. This clearance exists between the premixed gas burner element of the burner deck unit and the first and / or second cavity wall portions of the premixed gas burner. By positioning the tab base at a distance greater than twice the plate thickness plus the thickness of the premixed gas burner element from the main fold line, sufficient space is ensured to accommodate the premixed gas burner element in the cavity clearance. By providing a tab on the metal plate to be bent, the position on the second fold line is accurately defined, and the height of the cavity, i.e., the distance between the first cavity wall portion and the second cavity wall portion, is accurately defined. The predetermined stroke length of the punch also contributes to accurately obtaining the height of the cavity. In known manufacturing methods of premixed gas burners, a force-limited punch is used to attach premixed burner elements such as flame support parts to the cavity. However, by using a punch with a predetermined stroke length instead, since the end point of the punch stroke is accurately known in advance, the movement of the punch can stop at the correct position, and the desired cavity height can be realized. As described above, when using the method according to the second aspect of the present invention, in any of its variations, when the tab is bent on the secondary fold line, no or almost no dimples are formed. Thereby, the cavity in which the premixed gas burner element of the burner deck unit is arranged is accurately formed. Thereby, the risk of premixed gas leaking through the cavity is reduced.

[0043] In one embodiment, the main fold line and / or the secondary fold line is a straight line. Alternatively, the main fold line and / or the secondary fold line is a straight line.

[0044] In one embodiment, the metal plate is folded on the main fold line, and due to this folding, the angle between the primary part of the metal plate and the secondary part of the metal plate is 80° to 100°, optionally 90°.

[0045] In one embodiment, after this bending, the secondary part of the metal plate is bent along the secondary fold line so that the angle between the tab and a part of the secondary part of the metal plate located between the main fold line and the secondary fold line is between 80° and 100°, optionally 90°. Thereby, the tab and / or the primary part of the metal plate will cover at least a part of the premixed gas burner element of the burner deck unit.

[0046] In one embodiment, the metal plate is bent along the main fold line, the secondary part of the metal plate is bent along the secondary fold line, and after this folding, the tab and the primary part of the metal plate extend parallel to each other or at an angle of 30° or less.

[0047] In one embodiment, the premix burner element is a burner deck, a flame support, a burner deck unit, or a support portion of a burner deck unit.

Brief Description of the Drawings

[0048] Hereinafter, the present invention will be described in more detail with reference to the drawings. In the drawings, exemplary embodiments of the present invention are shown in a non-limiting manner.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9a

Figure 9b

Figure 10a

Figure 10b

Figure 11a

Figure 11b

Mode for Carrying Out the Invention

[0049] FIG. 1 schematically shows an embodiment of a premixed gas burner 1 according to the first aspect of the present invention. The premixed gas burner 1 includes a non-cylindrical burner deck unit 10 and a metal frame 20. The metal frame 20 includes a mounting plate 21 that enables the premixed gas burner 1 to be mounted on an appliance, such as a heating appliance. In the case of the premixed gas burner according to FIG. 1, the fuel gas is mixed with air or oxygen or other oxidant gas to form a premixed gas. This premixing is performed upstream of the operating burner deck area of the premixed gas burner, and combustion of the premixed gas is performed in the adjacent operating burner deck area. The fuel gas is, for example, natural gas, methane, hydrogen, or a mixture of any of these.

[0050] FIG. 2 schematically shows a first example of a burner deck unit 10 for a premixed gas burner 1 according to the first aspect of the present invention. In the example of FIG. 2, the burner deck unit includes a flame support portion 11. The flame support portion 11 includes an operating burner deck area 12. In the example of FIG. 2, the flame support portion 11 is made of a metal plate, for example, a flat metal plate. The operating burner deck area 12 is provided with a gas outlet. During the use of the premixed gas burner 1, after the premixed gas passes through the gas outlet of the operating burner deck area 12, it is burned adjacent to the operating burner deck area 12. The operating burner deck area 12 is provided with a plurality of gas outlets arranged in a normal pattern. This pattern is formed, for example, by holes and / or slots penetrating a metal plate, and these holes form the gas outlets. The burner deck unit further includes a periphery 13 and a support portion 14. The support portion 14 exists between the operating burner deck area 12 and a support portion edge 16 formed by at least a part of the periphery 13 of the burner deck unit. The support portion 14 has a thickness of the support portion and extends on a support portion surface perpendicular to the thickness of the support portion. In the example of FIG. 2, the support portion 14 extends around the operating burner deck area 12 and is formed by a rim 15 that is integral with the flame support portion 11, that is, a part of the plate forming the flame support portion 11. In the example of FIG. 2, the periphery 13 of the burner deck unit 10 is entirely formed by the periphery of the flame support portion 11. In the example of FIG. 2, the support portion does not include holes and / or slots. However, it is possible for the support portion to have holes and / or slots. However, such holes and / or slots in the support portion are not part of the operating burner deck area 12. This is because the arrangement of the support portion in the cavity prevents the flow of the premixed gas through the holes and / or slots in the support portion, so during operation, the premixed gas does not flow through and burn through such holes and / or slots.

[0051] FIG. 3 schematically shows a second example of the burner deck unit 10 for the premixed gas burner 1 according to the first aspect of the present invention. In the example of FIG. 3, the burner deck unit includes a flame support portion 11. The flame support portion 11 includes an operating burner deck area 12. In the example of FIG. 3, the flame support portion 11 is made of a woven wire mesh. The actuating burner deck area 12 is provided with a gas outlet. During the use of the premixed gas burner 1, after the premixed gas passes through the gas outlet of the actuating burner deck area 12, it is burned adjacent to the actuating burner deck area 12. The woven wire mesh has a plurality of metal mesh wires, and the gas outlet is formed by adjacent groups of metal mesh wires. In the example of FIG. 3, the woven wire mesh consists of a metallic warp and a metallic weft. The burner deck unit further includes a periphery 13 and a support portion 14. The support portion 14 exists between the actuating burner deck area 12 and a support portion edge 16 formed by at least a part of the periphery 13 of the burner deck unit. In the example of FIG. 3, the support portion 14 is formed by a rim 15 connected to the woven wire mesh of the flame support portion 11. The rim 15 is formed, for example, by a metal plate welded or clamped to the woven wire mesh. In the example of FIG. 3, the periphery 13 of the burner deck unit 10 is formed by the periphery of the rim 15 that forms the support portion 14. The support portion 14 has a thickness of the support portion and extends on a support portion surface perpendicular to the thickness of the support portion. In a modification of the embodiment of FIG. 3, no rim is added to the flame support portion 12, and the support portion is formed by the woven wire mesh. In that case, the openings between adjacent wires of the woven wire mesh in the support portion are not part of the actuating burner deck area 12. This is because the arrangement of the support portion in the cavity prevents the flow of the premixed gas through the holes and / or slots of the support portion, so that the premixed gas does not flow through such openings and burn.

[0052] FIG. 4 schematically shows, in partial cross-section, a first embodiment of a premixed gas burner according to a first aspect of the present invention. The premixed gas burner of the embodiment of FIG. 4 includes a non-cylindrical burner deck unit 10 and a metal frame 20. In this embodiment, for example, any of the burner deck units 10 according to FIG. 2 or FIG. 3 (including the modified examples described in the embodiment of FIG. 3) can be used. The metal frame 20 is adapted to hold the non-cylindrical burner deck unit 10. The metal frame 20 is formed, for example, by one or a plurality of metal plates, for example at least one curved metal plate. In the embodiment of FIG. 4, the metal frame 20 further includes a mounting plate 21 for mounting the premixed gas burner to an appliance such as a heating appliance, for example a building heating system or a water heater system. In the embodiment of FIG. 4, the premixed gas burner further includes a cavity in which at least a part of the support portion 14 of the burner deck unit 10 is disposed. The cavity includes a cavity opening 26 and a cavity inner wall. The cavity inner wall includes a cavity end wall portion 25, a first cavity wall portion 22, and a second cavity wall portion 23. At least a part of the support portion 14 of the burner deck unit 10 extends into the cavity through the cavity opening 26. The cavity end wall portion 25 is disposed opposite to the cavity opening 26. The second cavity wall portion 23 is disposed opposite to the first cavity wall portion 22. The first cavity wall portion 22 and the second cavity wall portion 23 extend parallel or non-perpendicular to the support portion surface, and the cavity end wall portion 25 extends between the first cavity wall portion 22 and the second cavity wall portion 23. The first cavity wall portion 22 is formed by the cavity boundary region of the metal frame 20.

[0053] In the embodiment of FIG. 4, the distance between the first cavity wall portion 22 and the second cavity wall portion 23 is greater than the thickness of the support portion. There is a clearance 24 between at least a part of the support portion 14 disposed in the cavity and at least one of the first cavity wall portion 22 and the second cavity wall portion 23.

[0054] In the embodiment of FIG. 4, when both the frame and the burner deck unit are measured in a state where they are at the ambient temperature, the support portion 14 extends between the first cavity wall portion 22 and the second cavity wall portion 23 over a length corresponding to at least half of the predicted thermal shrinkage of the burner deck unit 10 on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Further, when both the frame and the burner deck unit are measured in a state where they are at the ambient temperature, the cavity end wall portion 25 is spaced apart from the support portion edge 16 by a distance corresponding to at least half of the predicted thermal expansion of the burner deck unit 10 on the support portion plane when heating the burner deck unit 10 from the ambient temperature to the maximum operating temperature.

[0055] In the embodiment of FIG. 4, the cavity is defined by a cavity boundary region of the frame 20, a counter plate 32 facing the cavity boundary region of the frame, and a spacer 31 disposed between the cavity boundary surface of the frame and the counter plate 32. In this embodiment, the counter plate 32 defines the second cavity wall portion 23, and the spacer 31 defines the distance between the first cavity wall portion 22 and the second cavity wall portion 23. In this embodiment, one side of the spacer 31 defines the end cavity wall portion 25. Optionally, the counter plate 32 is connected to the metal frame 20, for example, by welding (e.g., one or more spot welds), or by rivets or bolts. Optionally, the spacer 31 is connected to the metal frame 20, for example, by welding (e.g., one or more spot welds), or by one or more rivets. Optionally, the counter plate 32 is connected to the spacer 31, and the spacer 31 is connected to the metal frame 20. In the embodiment of FIG. 4, the counter plate 32 and the spacer 31 are composed of separate parts. Optionally, the counter plate 32 and / or the spacer 31 is made of metal, such as steel, stainless steel, or aluminum. Alternatively, the counter plate 32 and / or the spacer 31 is made of resin, such as fiber-reinforced resin.

[0056] In the embodiment of FIG. 4, the flame support has an inner surface 17 facing the operating burner deck area, and the premix gas burner further includes a gas distribution plate 30, which is disposed at a distance adjacent to the inner surface 17 of the flame support. In the embodiment of FIG. 4, the gas distribution plate 30 is attached to the counter plate 32.

[0057] FIG. 5 schematically shows in partial cross-section a second embodiment of a premix gas burner according to a first aspect of the present invention. The premix gas burner of the embodiment of FIG. 5 includes a non-cylindrical burner deck unit 10 and a metal frame 20. In this embodiment, any of the burner deck units 10 according to, for example, FIG. 2 or FIG. 3 (including the described variations of the embodiment of FIG. 3) can be used. The metal frame 20 is adapted to hold the non-cylindrical burner deck unit 10. The metal frame 20 is formed, for example, by one or more metal plates, such as at least one curved metal plate. In the embodiment of FIG. 5, the metal frame 20 further includes a mounting plate 21 for attaching the premix gas burner to an appliance, such as a heating appliance for a building heating system or a water heater system. In the embodiment of FIG. 5, the premixed gas burner further includes a cavity in which at least a part of the support portion 14 of the burner deck unit 10 is disposed. The cavity includes a cavity opening 26 and a cavity inner wall. The cavity inner wall includes a cavity end wall portion 25, a first cavity wall portion 22, and a second cavity wall portion 23. At least a part of the support portion 14 of the burner deck unit 10 extends into the cavity through the cavity opening 26. The cavity end wall portion 25 is disposed opposite to the cavity opening 26. The second cavity wall portion 23 is disposed opposite to the first cavity wall portion 22. The first cavity wall portion 22 and the second cavity wall portion 23 extend parallel or non-perpendicular to the support portion surface, and the cavity end wall portion 25 extends between the first cavity wall portion 22 and the second cavity wall portion 23. The first cavity wall portion 22 is formed by a cavity boundary region of the metal frame 20.

[0058] In the embodiment of FIG. 5, the distance between the first cavity wall portion 22 and the second cavity wall portion 23 is greater than the thickness of the support portion. A clearance 24 exists between at least a part of the support portion 14 disposed in the cavity and at least one of the first cavity wall portion 22 and the second cavity wall portion 23.

[0059] In the embodiment of FIG. 5, when measured with both the frame and the burner deck unit at the ambient temperature, the support portion 14 extends between the first cavity wall portion 22 and the second cavity wall portion 23 over a length corresponding to at least half of the expected thermal shrinkage of the burner deck unit 10 on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Further, when measured with both the frame and the burner deck unit at the ambient temperature, the cavity end wall portion 25 is spaced from the support portion edge 16 by a distance corresponding to at least half of the expected thermal expansion of the burner deck unit 10 on the support portion surface when heating the burner deck unit 10 from the ambient temperature to the maximum operating temperature.

[0060] In the embodiment of FIG. 5, the cavity is defined by metal frames 20 on two sides of the cavity. Further, a counter plate 32 is provided facing the first cavity wall portion 22. In this embodiment, the counter plate 32 defines the second cavity wall portion 23, and the end wall portion 27 of the frame 20 defines the distance between the first cavity wall portion 22 and the second cavity wall portion 23. In this embodiment, the end wall portion 27 of the frame 20 forms the end cavity wall portion 25. Optionally, the counter plate 32 is connected to the metal frame 20, for example, by welding (for example, one or more spot welds) or rivets. Optionally, the counter plate 32 is made of metal such as steel, stainless steel, or aluminum. Alternatively, the counter plate 32 is made of resin such as fiber-reinforced resin.

[0061] In the embodiment of FIG. 5, the flame support has an inner surface 17 facing the working burner deck area, and the premixed gas burner further includes a gas distribution plate 30, and this gas distribution plate 30 is arranged adjacent to and spaced from the inner surface 17 of the flame support. In the embodiment of FIG. 5, the gas distribution plate 30 is attached to the counter plate 32.

[0062] FIG. 6 schematically shows in partial cross-section a third embodiment of a premixed gas burner according to a first aspect of the present invention. The premixed gas burner of the embodiment of FIG. 6 includes a non-cylindrical burner deck unit 10 and a metal frame 20. In this embodiment, any of the burner deck units 10 according to, for example, FIG. 2 or FIG. 3 (including the described variations of the embodiment of FIG. 3) can be used. The metal frame 20 is adapted to hold the non-cylindrical burner deck unit 10. The metal frame 20 is formed, for example, by one or more metal plates, for example at least one curved metal plate. In the embodiment of FIG. 6, the metal frame 20 further comprises a mounting plate 21 for mounting a premix gas burner to an appliance such as a heating appliance, for example a building heating system or a water heater system. In the embodiment of FIG. 6, the premix gas burner further comprises a cavity in which at least a part of the support portion 14 of the burner deck unit 10 is disposed. The cavity comprises a cavity opening 26 and a cavity inner wall. The cavity inner wall comprises a cavity end wall portion 25, a first cavity wall portion 22 and a second cavity wall portion 23. At least a part of the support portion 14 of the burner deck unit 10 extends into the cavity through the cavity opening 26. The cavity end wall portion 25 is disposed opposite to the cavity opening 26. The second cavity wall portion 23 is disposed opposite to the first cavity wall portion 22. The first cavity wall portion 22 and the second cavity wall portion 23 extend parallel or non-perpendicular to the support portion surface, and the cavity end wall portion 25 extends between the first cavity wall portion 22 and the second cavity wall portion 23. The first cavity wall portion 22 is formed by the cavity boundary region of the metal frame 20.

[0063] In the embodiment of FIG. 6, the distance between the first cavity wall portion 22 and the second cavity wall portion 23 is greater than the thickness of the support portion. There is a clearance 24 between at least a part of the support portion 14 disposed in the cavity and at least one of the first cavity wall portion 22 and the second cavity wall portion 23.

[0064] In the embodiment of FIG. 6, when the frame and the burner deck unit are both measured at the ambient temperature, the support portion 14 extends between the first cavity wall portion 22 and the second cavity wall portion 23 over a length corresponding to at least half of the expected thermal contraction of the burner deck unit 10 on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Further, when both the frame and the burner deck unit are measured at the ambient temperature, the cavity end wall portion 25 is spaced apart from the support portion edge 16 by a distance corresponding to at least half of the expected thermal expansion of the burner deck unit 10 on the support portion surface when heating the burner deck unit 10 from the ambient temperature to the maximum operating temperature.

[0065] In the embodiment of FIG. 6, the flame support portion has an inner surface 17 facing the operating burner deck area, and the premix gas burner further includes a gas distribution plate 30, and this gas distribution plate 30 is arranged adjacent to and spaced from the inner surface 17 of the flame support portion.

[0066] In the embodiment of FIG. 6, the cavity is defined by the metal frame 20 on two sides of the cavity. In this embodiment, the gas distribution plate defines the second cavity wall portion 23, and the end wall portion 27 of the frame 20 defines the distance between the first cavity wall portion 22 and the second cavity wall portion 23. In this embodiment, the end wall portion 27 of the frame 20 forms the end cavity wall portion 25. Optionally, the gas distribution plate 30 is connected to the metal frame 20 by, for example, welding (e.g., one or more spot welds), or by rivets and / or bolts.

[0067] FIG. 7 schematically shows, in partial cross-section, a fourth embodiment of a premix gas burner according to a first aspect of the present invention. The premixed gas burner of the embodiment shown in FIG. 7 includes a non-cylindrical burner deck unit 10 and a metal frame 20. In this embodiment, any one of the burner deck units 10 according to, for example, FIG. 2 or FIG. 3 (including the modified examples described in the embodiment of FIG. 3) can be used. The metal frame 20 is adapted to hold the non-cylindrical burner deck unit 10. The metal frame 20 is formed by, for example, one or a plurality of metal plates, for example, at least one curved metal plate. In the embodiment shown in FIG. 7, the metal frame 20 further includes a mounting plate 21 for mounting the premixed gas burner to an appliance such as a heating appliance, for example, a building heating system or a water heater system. In the embodiment shown in FIG. 7, the premixed gas burner further includes a cavity in which at least a part of the support portion 14 of the burner deck unit 10 is disposed. The cavity includes a cavity opening 26 and a cavity inner wall. The cavity inner wall includes a cavity end wall portion 25, a first cavity wall portion 22, and a second cavity wall portion 23. At least a part of the support portion 14 of the burner deck unit 10 extends into the cavity through the cavity opening 26. The cavity end wall portion 25 is disposed opposite to the cavity opening 26. The second cavity wall portion 23 is disposed opposite to the first cavity wall portion 22. The first cavity wall portion 22 and the second cavity wall portion 23 extend parallel or non-perpendicular to the support portion surface, and the cavity end wall portion 25 extends between the first cavity wall portion 22 and the second cavity wall portion 23. The first cavity wall portion 22 is formed by the cavity boundary region of the metal frame 20.

[0068] In the embodiment shown in FIG. 7, the distance between the first cavity wall portion 22 and the second cavity wall portion 23 is greater than the thickness of the support portion. A clearance 24 exists between at least a part of the support portion 14 disposed in the cavity and at least one of the first cavity wall portion 22 and the second cavity wall portion 23.

[0069] In the embodiment of FIG. 7, when the frame and the burner deck unit are both measured at the ambient temperature, the support portion 14 extends between the first cavity wall portion 22 and the second cavity wall portion 23 over a length corresponding to at least half of the expected thermal contraction of the burner deck unit 10 on the support portion surface when cooling the burner deck unit from the maximum operating temperature to the ambient temperature. Further, when both the frame and the burner deck unit are measured at the ambient temperature, the cavity end wall portion 25 is spaced apart from the support portion edge 16 by a distance corresponding to at least half of the expected thermal expansion of the burner deck unit 10 on the support portion surface when heating the burner deck unit 10 from the ambient temperature to the maximum operating temperature.

[0070] In the embodiment of FIG. 7, the flame support portion has an inner surface 17 facing the operating burner deck area, and the premix gas burner further includes a gas distribution plate 30, and this gas distribution plate 30 is arranged adjacent to and spaced from the inner surface 17 of the flame support portion.

[0071] In the embodiment of FIG. 7, the cavity is defined by a metal frame 20 on one side of the cavity. In this embodiment, the gas distribution plate defines the second cavity wall portion 23. Further, the gas distribution plate 30 has an end wall portion 33 that defines the distance between the first cavity wall portion 22 and the second cavity wall portion 23. In this embodiment, the end wall portion 33 of the gas distribution plate 30 forms the end cavity wall portion 25. Optionally, the gas distribution plate 30 is connected to the metal frame 20 by, for example, welding (e.g., one or more spot welds), or by rivets and / or bolts.

[0072] FIG. 8 shows an example of a metal plate 100 that can be used in the method according to the first aspect of the present invention and the method according to the second aspect of the present invention.

[0073] In the method according to the first aspect of the present invention and the method according to the second aspect of the present invention, a premixed gas burner is manufactured, and in the manufacturing process, a metal plate is bent to form a cavity in which a support portion of the burner deck unit or other elements of the premixed gas burner are accommodated with a clearance.

[0074] FIG. 8 shows an example of a metal plate 100 that can be used in these methods. The metal plate 100 has a first portion 101 that forms a primary portion in the method and a second portion that forms a secondary portion 102 in the method. The first portion 101 and the second portion 102 are separated from each other by a main fold line 111. The main fold line 111 is optionally scored, but this is not essential. The metal plate 100 has a plate thickness and includes at least one tab 105 on the first side of the metal plate 100. The tab 105 extends from a tab base 106 to a tab top 107. The tab base 106 is disposed at a distance from the main fold line 111, and that distance is greater than twice the plate thickness plus the thickness of the support portion or the thickness of the premixed gas burner element to be supported by the metal plate. The tab top 107 is further away from the main fold line 111 than the tab base 106. In the example of FIG. 8, the metal plate 100 has a plurality of tabs 105. The metal plate 100 further has a second fold line 112 located at the tab base 106. The secondary fold line 112 is optionally scored, but this is not essential.

[0075] In the embodiment of FIG. 8, the main fold line 111 and the secondary fold line 112 are each straight lines.

[0076] FIGS. 9a and 9b show the steps in an embodiment of a first variant of the method according to the first aspect of the present invention and / or a first variant of the method according to the second aspect of the present invention.

[0077] As shown in FIG. 9a, in this embodiment, first, the metal plate 100 of FIG. 8 is bent along the main folding line 111. By this bending, a primary portion 121 of the metal plate is formed which is angled with respect to the secondary portion 122 of the metal plate. The primary portion is disposed on the first side of the main folding line 111, and the secondary portion is disposed on the second side of the main folding line 111. The first side and the second side face each other. The secondary portion 122 has a tab 105.

[0078] Next, in this embodiment, at least a part of the support portion 14 of the burner deck unit (the first side of the present invention), or the premixed gas burner element 114 (the second side of the present invention) supported by the metal plate, is disposed on or in the vicinity of the primary portion 121 of the metal plate.

[0079] Next, in this embodiment, a punch having a predetermined stroke length is used to bend the secondary portion 122 of the metal plate 100 along the secondary folding line 112. The tab 105 is configured to extend over at least a part of the support portion of the burner deck unit 14 (the first side of the present invention), or the premixed gas burner element 114 (the second side of the present invention) to be supported by the metal plate. The tab 105 is disposed at an angle with respect to a part 108 of the secondary portion of the metal plate located between the main folding line 111 and the secondary folding line 112. Thus, in the method according to the first side of the present invention, at least a part of the inner wall of the cavity of the premixed burner according to the first side of the present invention is formed by the primary portion 121 of the metal plate defining one of the first cavity wall portion or the second cavity wall portion, the tab 105 defining the other of the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the metal plate located between the main folding line and the secondary folding line defining the cavity end wall portion. Similarly, in the method according to the second aspect of the present invention, at least a part of the cavity inner wall of the cavity of the premix burner in which the premix gas burner element is disposed in the cavity is thus formed by the primary portion 121 of the metal plate defining one of the first cavity wall portion or the second cavity wall portion, the tab 105 defining the other of the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the empty metal plate located between the main fold line and the sub-fold line defining the cavity end wall portion.

[0080] In the embodiments of FIGS. 9a and 9b, the metal plate 100 is bent along the main fold line 111 such that the angle between the primary portion 121 of the metal plate and the secondary portion 122 of the metal plate is between 80° and 100°, optionally 90°, after this bending.

[0081] In the embodiments of FIGS. 9a and 9b, the secondary portion 122 of the metal plate is bent along the sub-fold line 112 such that the angle between the tab 105 and a part 108 of the secondary portion of the metal plate located between the main fold line and the sub-fold line is between 80° and 100°, optionally 90°, after this bending.

[0082] In the embodiments of FIGS. 9a and 9b, the metal plate 100 is bent along the main fold line 111, the secondary portion of the metal plate is bent along the sub-fold line 112, and after this bending, the tab 105 and the primary portion 101 of the metal plate 100 extend parallel to each other or at an angle of 30° or less.

[0083] FIGS. 10a and 10b show the steps in an embodiment of a second variant of the method according to the first aspect of the present invention and / or a second variant of the method according to the second aspect of the present invention.

[0084] As shown in FIG. 10a, in this embodiment, first, the metal plate 100 of FIG. 8 is bent along the main fold line 111. By this bending, a primary portion 121 of the metal plate is formed which is angled with respect to the secondary portion 122 of the metal plate. The primary portion is disposed on the first side of the main fold line 111, and the secondary portion is disposed on the second side of the main fold line 111. The first side and the second side face each other. The secondary portion 122 has a tab 105.

[0085] Next, in this embodiment, at least a part of the support portion 14 of the burner deck unit (the first side surface of the present invention), or the premixed gas burner element 114 supported by the metal plate (the second side surface of the present invention), is disposed on or adjacent to the primary portion 121 of the metal plate.

[0086] Next, in this embodiment, a punch having a predetermined stroke length is used to bend the secondary portion 122 of the metal plate 100 on the secondary fold line 112. The tab 105 extends parallel to at least a part of the support portion 14 (the first side surface of the present invention), or the premixed gas burner element 114 supported by the metal plate (the second side surface of the present invention), but does not overlap. The tab 105 is disposed at an angle with respect to a part 108 of the secondary portion of the metal plate located between the main fold line 111 and the secondary fold line 112. Thus, in the method according to the first side surface of the present invention, at least a part of the cavity inner wall of the cavity of the premixed burner according to the first side surface of the present invention is formed together with the primary portion 121 of the metal plate that defines the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the metal plate that defines the cavity end wall portion located between the main fold line and the secondary fold line. Similarly, in the method according to the second side surface of the present invention, at least a part of the cavity inner wall of the cavity of the premixed burner in which the premixed gas burner element is disposed is formed together with the primary portion 121 of the metal plate that defines the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the empty metal plate located between the main fold line and the secondary fold line that defines the cavity end wall portion.

[0087] In the embodiments of FIGS. 10a and 10b, after this bending, the metal plate 100 is bent along the main fold line 111 such that the angle between the primary portion 121 of the metal plate and the secondary portion 122 of the metal plate is between 80° and 100°, optionally 90°.

[0088] In the embodiments of FIGS. 10a and 10b, after this bending, the secondary portion 122 of the metal plate is bent along the secondary fold line 112 such that the angle between the tab 105 and a part 108 of the secondary portion of the metal plate located between the main fold line and the secondary fold line is between 80° and 100°, optionally 90°.

[0089] In the embodiments of FIGS. 10a and 10b, the metal plate 100 is bent along the main fold line 111, and the secondary portion of the metal plate is bent along the secondary fold line 112. After this folding, the tab 105 and the primary portion 101 of the metal plate 100 extend parallel to each other or at an angle of 30° or less.

[0090] FIGS. 11a and 11b show the steps in an embodiment of a third variation of the method according to the first aspect of the present invention and / or a third variation of the method according to the second aspect of the present invention.

[0091] As shown in FIG. 11a, in this embodiment, first, the metal plate 100 of FIG. 8 is bent along the main fold line 111. By this bending, a primary portion 121 of the metal plate is formed which is angled with respect to the secondary portion 122 of the metal plate. The primary portion is disposed on the first side of the main fold line 111, and the secondary portion is disposed on the second side of the main fold line 111. The first side and the second side face each other. The secondary portion 122 has a tab 105.

[0092] Next, in this embodiment, at least a part of the support portion 14 of the burner deck unit (first aspect of the present invention), or the premixed gas burner element 114 (second aspect of the present invention) adjacent to and / or supported on the tab of the metal plate, does not extend beyond the base of the tab. Next, in the present embodiment, using a punch having a predetermined stroke length, the secondary portion 122 of the metal plate 100 is bent along the secondary fold line 112. The tab 105 will extend over at least a part of the support portion 14 (the first aspect of the present invention) or the premixed gas burner element 114 (the second aspect of the present invention) supported by the metal plate. The tab 105 is disposed at an angle with respect to a part 108 of the secondary portion of the metal plate located between the main fold line 111 and the secondary fold line 112. Thus, in the method according to the first aspect of the present invention, at least a part of the cavity inner wall of the cavity of the premixed burner according to the first aspect of the present invention between the primary portion of the metal plate and the tab of the metal plate is composed of the tab 105 of the metal plate defining the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the metal plate located between the main fold line and the secondary fold line defining the cavity end wall portion. Similarly, in the method according to the second aspect of the present invention, at least a part of the cavity inner wall of the premixed burner in which the premixed gas burner element is disposed between the primary portion 121 of the metal plate and the tab 105 of the metal plate in the cavity is composed of the tab of the metal plate defining the first cavity wall portion or the second cavity wall portion, and a part 108 of the secondary portion of the metal plate located between the main fold line and the secondary fold line defining the cavity end wall portion.

[0093] In the embodiments of FIGS. 11a and 11b, after this bending, the metal plate 100 is bent along the main fold line 111 such that the angle between the primary portion 121 and the secondary portion 122 of the metal plate is between 80° and 100°, optionally 90°.

[0094] In the embodiments of FIGS. 11a and 11b, after this bending, the secondary portion 122 of the metal plate is bent along the secondary fold line 112 such that the angle between the tab 105 and a part 108 of the secondary portion of the metal plate located between the main fold line and the secondary fold line is between 80° and 100°, optionally 90°.

[0095] In the embodiments of FIGS. 11a and 11b, the metal plate 100 is bent along the main fold line 111, and the secondary portion of the metal plate is bent along the secondary fold line 112. After this folding, the tab 105 and the primary portion 101 of the metal plate 100 extend parallel to each other or at an angle of 30° or less.

Claims

Claim 1 A premixed gas burner comprising a non-cylindrical burner deck unit and a metal frame, the non-cylindrical burner deck unit having a flame support portion, the flame support portion having an operating burner deck area with a gas discharge port, and during use adjacent to the operating burner deck area, the premixed gas being burned after flowing through the gas discharge port, the burner deck unit comprising a periphery and a support portion, the support portion being present between the operating burner deck area and a support portion edge formed by at least a part of the periphery of the burner deck unit, the support portion having a thickness of the support portion and extending to a support portion surface perpendicular to the thickness of the support portion, the metal frame being adapted to hold the non-cylindrical burner deck unit, the premixed gas burner further comprising a cavity, in which at least a part of the support portion of the burner deck unit is disposed, the cavity comprising a cavity opening and a cavity inner wall, through the cavity opening, at least a part of the support portion of the burner deck unit extends into the cavity, the cavity inner wall having a cavity end wall portion facing the cavity opening, a first cavity wall portion, and a second cavity wall portion disposed opposite the first cavity wall portion, the first cavity wall portion and the second cavity wall portion extending parallel or non-perpendicular to the support portion surface, and the cavity end wall portion extending between the first cavity wall portion and the second cavity wall portion, the first cavity wall portion being defined by a cavity boundary region of the metal frame, the distance between the first cavity wall portion and the second cavity wall portion being greater than the thickness of the support portion, When both the frame and the burner deck unit are at the ambient temperature, when cooling the burner deck unit from the maximum operating temperature to the ambient temperature, the support portion extends between the first cavity wall portion and the second cavity wall portion over a length corresponding to at least half of the expected thermal contraction of the burner deck unit on the support portion surface, and the cavity end wall portion is separated from the support portion edge by a distance that is at least half of the expected thermal expansion of the burner deck unit on the support portion surface when heating the burner deck unit from the ambient temperature to the maximum operating temperature. Premixed gas burner. **Claim 2** The cavity wall is further defined by a counter plate facing the cavity boundary region of the frame and a spacer disposed between the cavity interface surface of the frame and the counter plate. The counter plate defines the second cavity wall portion, and the spacer defines the cavity end wall portion. The premixed gas burner according to claim 1. **Claim 3** The flame support portion has an inner surface facing the operating burner deck area, the premixed gas burner further has a gas distribution plate, the gas distribution plate is spaced adjacent to the inner surface of the flame support portion, and a part of the gas distribution plate defines the second cavity wall portion. The premixed gas burner according to claim 1 or 2. **Claim 4** The inner cavity wall is defined by the gas distribution plate on at least two sides of the cavity. The premixed gas burner according to claim 3. **Claim 5** The inner cavity wall is defined by the metal frame on at least two sides of the cavity. The premixed gas burner according to claim 1 or 3. **Claim 6** The distance between the part of the support portion present in the cavity and the first cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.3 mm to 1.0 mm, for example 0.4 mm, and / or The distance between the part of the support portion present in the cavity and the second cavity wall portion is 0.05 mm to 2.5 mm, optionally 0.3 mm to 1.0 mm, for example 0.4 mm. The premixed gas burner according to any one of claims 1 to 5. **Claim 7** The flame support part is a woven wire mesh or includes the woven wire mesh. The woven wire mesh includes a plurality of metal mesh wires, and the gas discharge port is formed by adjacent groups of metal mesh wires. The premixed gas burner according to any one of claims 1 to 6.

8. The flame support part is a metal plate or includes the metal plate. The metal plate has a plurality of holes, and the gas discharge port is formed by the holes in the metal plate. The premixed gas burner according to any one of claims 1 to 6.

9. The flame support part extends partially or entirely in a plane or a curved surface. The premixed gas burner according to any one of claims 1 to 8.

10. The frame further includes a mounting plate for installing the premixed gas burner on a heating appliance. The premixed gas burner according to any one of claims 1 to 9.

11. The first cavity wall part and / or the second cavity wall part extend parallel to the support part surface or at an angle of 30° or less. The premixed gas burner according to any one of claims 1 to 10.

12. The support part is formed by the flame support part or by a rim connected to the flame support part. The premixed gas burner according to any one of claims 1 to 11.

13. A method for manufacturing a premixed burner according to any one of claims 1 to 12, a step of bending a metal plate along a main fold line, the metal plate having a plate thickness and including at least two tabs on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding twice the plate thickness to the thickness of the support part, the tab top being further away from the main fold line than the tab base, and the primary part of the metal plate being angled with respect to the secondary part of the metal plate, the primary part being disposed on a first side of the main fold line, the secondary part being disposed on a second side of the main fold line, the first side and the second side facing each other, and the secondary part having the tab, a step of disposing at least a part of the support part of the burner deck unit adjacent to and / or on the primary part of the metal plate, A step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, wherein the secondary fold line is disposed on the tab base, the tab extends over at least a part of the support portion of the burner deck unit, the tab is disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby the primary portion of the metal plate defining one of the first cavity wall portion or the second cavity wall portion, the tab defining the other of the first cavity wall portion or the second cavity wall portion, and a portion of the secondary portion of the metal plate defining the cavity end wall portion located between the main fold line and the secondary fold line together form at least a part of the cavity inner wall of the cavity of the premix burner according to the first aspect of the present invention. A method of manufacturing a premix burner comprising the same.

14. A method of manufacturing a premix burner according to any one of claims 1 to 13, A step of bending a metal plate along a main fold line, the metal plate having a plate thickness, the metal plate having at least two tabs on a first side thereof, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding the thickness of the support portion to twice the plate thickness, the tab top being further away from the main fold line than the tab base, and by a fold forming the primary portion of the metal plate disposed at an angle with respect to the secondary portion of the metal plate, the primary portion is disposed on a first side of the main fold line, the secondary portion is disposed on a second side of the main fold line, the first side and the second side face each other, and the secondary portion has the tab. A step of disposing at least a part of the support portion of the burner deck unit adjacent to and / or on the primary portion of the metal plate. The step of bending the secondary portion of the metal plate along a secondary fold line using a punch having a predetermined stroke length, wherein the secondary fold line is disposed on the tab base, the tab extends parallel to at least a portion of the support portion of the burner deck unit without overlapping, the tab is disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the secondary fold line, whereby the primary portion of the metal plate defining the first cavity wall portion or the second cavity wall portion and a portion of the secondary portion of the metal plate defining the cavity end wall portion located between the main fold line and the secondary fold line together form at least a part of the cavity inner wall of the cavity of the premix burner according to the first side of the present invention. A method for manufacturing a premix burner comprising the same.

15. A method for manufacturing a premix burner according to any one of claims 1 to 14, The step of bending a metal plate along a main fold line, the metal plate having a plate thickness, comprising at least two tabs on a first side of the metal plate, each tab extending from a tab base to a tab top, the tab base being disposed at a distance from the main fold line, the distance being greater than a value obtained by adding twice the plate thickness to the thickness of the support portion, the tab top being further away from the main fold line than the tab base, the primary portion of the metal plate disposed at an angle with respect to the secondary portion of the metal plate being formed by a fold line, the primary portion being disposed on a first side of the main fold line, the secondary portion being disposed on a second side of the main fold line, the first side and the second side facing each other, the secondary portion having the tab. The step of disposing at least a portion of the support portion of the burner deck unit adjacent to and / or on the tab of the metal plate so as not to extend beyond the base of the tab. bending the secondary portion of the metal plate along the sub-fold line using a punch having a predetermined stroke length, wherein the sub-fold line is disposed on the tab base, the tab extends over at least a part of the support portion of the burner deck unit, and the tab is disposed at an angle with respect to a portion of the secondary portion of the metal plate located between the main fold line and the sub-fold line, whereby the tab of the metal plate defining the first cavity wall portion or the second cavity wall portion, together with a portion of the secondary portion of the metal plate defining the cavity end wall portion located between the main fold line and the sub-fold line, forms at least a part of the cavity inner wall of the cavity of the premix burner according to the first side surface of the present invention between the primary portion of the metal plate and the tab of the metal plate, A method of manufacturing a premix burner comprising the same. **Claim 16** A water heater comprising the premix gas burner according to any one of claims 1 to 15.

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