Burner for stove

Abstract

To improve ignition performance, in a burner for a cooking stove having upper / lower two stages of flame holes which comprises a burner body 2 having inside / outside triple cylinder bodies, a lower burner cap 2 for defining lower-stage flame holes 4L between an outside cylinder body 11 of the burner body 1 and itself, and an upper burner cap 3 for defining upper-stage flame holes 4U between the lower burner cap 2 and itself, constitutes one of the lower-stage flame holes 4L located at one point in a peripheral direction at an ignition flame hole 4I, and ignites an air-fuel mixture injected from the ignition flame hole 4I by a spark discharge between a target part 24 located above the ignition flame hole 4I formed at the lower burner cap 2 and an ignition electrode 7.SOLUTION: There are arranged a pair of vertical longitudinal ribs 25 which are located at two points in a peripheral direction separated from each other in the peripheral direction so as to sandwich an ignition flame hole 4I, and made to abut on, or approach the other of a cylinder part 21 of an internal peripheral part of a lower burner cap 2 and an outside cylinder body 11 of a burner body 1 while protruding from either of the cylinder part and the outside cylinder body.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a burner for a stove having upper and lower two-stage flame ports.

Background Art

[0002] Conventionally, as this type of burner for a stove, there is a burner body having an outer cylinder, an intermediate cylinder, and an inner cylinder, which are three cylinders inside and outside, and a cylindrical portion that fits into the intermediate cylinder of the burner body is vertically provided on the inner peripheral portion, and a large number of lower-stage flame ports are defined with a circumferential interval between the outer cylinder of the burner body. An annular lower burner cap, and a cylindrical portion that fits into the inner cylinder of the burner body is vertically provided on the inner peripheral portion, and an annular upper burner cap that defines a large number of upper-stage flame ports with a circumferential interval from the lower burner cap. The mixture is supplied to the lower-stage flame port through a lower-stage flame port mixture chamber surrounded by the outer cylinder, the intermediate cylinder, and the lower burner cap of the burner body, and the intermediate cylinder, the inner cylinder, and the lower burner cap of the burner body. And the upper burner cap, and the mixture is supplied to the upper-stage flame port through the upper-stage flame port mixture chamber surrounded by the upper burner cap. (For example, see Patent Document 1). Further, in this device, one of the lower-stage flame ports located at one position in the circumferential direction is configured as an ignition flame port. And a target portion located above the ignition flame port is provided on the lower burner cap, and the mixture ejected from the ignition flame port is ignited by a spark discharge between the ignition electrode arranged to face the target portion and the target portion.

[0003] Here, in the burner for a stove of the above prior example, generally, in the lower-stage flame port mixture chamber, at a position circumferentially away from the ignition flame port, the mixture flows in with a motion component in a direction inclined with respect to the radial direction passing through the position. Therefore, the mixture swirls in the lower-stage flame port mixture chamber, and the mixture flows into the ignition flame port with a swirl component. As a result, the mixture is ejected from the ignition flame port in a direction inclined in the circumferential direction, and the ejection flow of the mixture deviates from the discharge gap between the ignition electrode and the target portion, and ignition failure is likely to occur.

Prior Art Documents

Patent Documents

[0004] Patent Document 1 Japanese Patent Application Laid-Open No. 2019-143959 Summary of the Invention Problems to be Solved by the Invention

[0005] In view of the above points, an object of the present invention is to provide a burner for a stove having upper and lower two-stage flame ports, which can improve the ignition performance. Means for Solving the Problems

[0006] In order to solve the above problems, the present invention is a burner for a stove having upper and lower two-stage flame ports, and includes a burner body having an outer cylinder, an intermediate cylinder, and an inner cylinder, which are three cylinders inside and outside; a cylindrical portion that fits into the intermediate cylinder of the burner body is vertically provided on the inner peripheral portion, and an annular lower burner cap that defines a number of lower flame ports with a circumferential interval between the outer cylinder of the burner body; a cylindrical portion that fits into the inner cylinder of the burner body is vertically provided on the inner peripheral portion, and an annular upper burner cap that defines a number of upper flame ports with a circumferential interval between the lower burner cap; the mixture is supplied to the lower flame ports through a lower-stage flame port mixture chamber surrounded by the outer cylinder, the intermediate cylinder, and the lower burner cap of the burner body, and the mixture is supplied to the upper flame ports through an upper-stage flame port mixture chamber surrounded by the intermediate cylinder, the inner cylinder, the lower burner cap, and the upper burner cap of the burner body. One of the lower flame ports located at one circumferential position is configured as an ignition flame port, a target portion is provided on the lower burner cap above the ignition flame port, and the mixture ejected from the ignition flame port is ignited by a spark discharge between the ignition electrode arranged to face the target portion and the target portion. In this case, a pair of longitudinally long ribs that protrude from one of the cylindrical portion on the inner peripheral portion of the lower burner cap and the outer cylinder of the burner body and abut or approach the other are provided at two circumferential positions separated in the circumferential direction so as to sandwich the ignition flame port in the lower-stage flame port mixture chamber.

[0007] According to the present invention, even if the air-fuel mixture swirls in the air-fuel mixture chamber for the lower flame port, after the air-fuel mixture flows upward from below between a pair of ribs in a state where the swirling component is removed, it flows into the ignition flame port, and the air-fuel mixture is ejected radially from the ignition flame port without tilting in the circumferential direction. As a result, the ejection flow of the air-fuel mixture from the ignition flame port does not deviate from the discharge gap between the ignition electrode and the target portion, and the ignition performance is improved.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0009] Referring to FIGS. 1 to 4, the burner for a stove according to an embodiment of the present invention has upper and lower two-stage flame ports to be described later, and includes a burner body 1, a lower burner cap 2, and an upper burner cap 3. The burner body 1 is made of sheet metal and has three concentric cylinders, namely an outer cylinder 11, an intermediate cylinder 12, and an inner cylinder 13. The lower burner cap 2 is annular, and a cylindrical portion 21 that fits into the intermediate cylinder 12 of the burner body 1 is vertically provided on the inner peripheral portion. The upper burner cap 3 is annular, and a cylindrical portion 31 that fits into the inner cylinder 13 of the burner body 1 is vertically provided on the inner peripheral portion. A large number of lower flame ports 4L are defined with a circumferential interval between the outer cylinder 11 of the burner body 1 and the lower burner cap 2, and a large number of upper flame ports 4U are defined with a circumferential interval between the lower burner cap 2 and the upper burner cap 3.

[0010] Specifically, an annular wall 22 that seats on the upper end of the outer cylinder 11 of the burner body 1 is vertically provided on the outer peripheral portion of the lower surface of the lower burner cap 2. An inwardly bent flange portion 11a is formed at the upper end of the outer cylinder 11, and the annular wall 22 seats on this inwardly bent flange portion 11a. A number of grooves serving as the lower flame ports 4L that are recessed upward from their lower ends are formed in the annular wall 22 at intervals in the circumferential direction. The lower ends of these grooves are blocked by the inwardly bent flange portion 11a, so that the lower flame ports 4L are defined between the outer cylinder 11 and the lower burner cap 2. In a portion located in the same orientation as a plurality of trivet claws (not shown), only the lower flame ports 4L are formed without forming the upper flame ports 4U in order to prevent the trivet claws from being touched by the flame and undergoing incomplete combustion.

[0011] The upper flame ports 4U are divided into two upper and lower parts, namely, an upper flame port part 4Ua and a lower flame port part 4Ub. Specifically, an annular wall 23 is erected on the outer peripheral portion of the upper surface of the lower burner cap 2, and a number of grooves serving as the lower flame port part 4Ub of the upper flame ports 4U that are recessed downward from their upper ends are formed in the annular wall 23 at intervals in the circumferential direction. Further, an annular wall 32 that seats on the annular wall 23 is vertically provided on the outer peripheral portion of the lower surface of the upper burner cap 3, and a number of grooves serving as the upper flame port part 4Ua of the upper flame ports 4U that are recessed upward from their lower ends are formed in the annular wall 32 at intervals in the circumferential direction and are offset in the circumferential direction with respect to the grooves serving as the lower flame port part 4Ub. Thereby, between the lower burner cap 2 and the upper burner cap 3, the upper flame port part 4Ua and the lower flame port part 4Ub are defined in a staggered pattern with their positions offset in the circumferential direction.

[0012] The burner for the stove further includes a pair of mixing pipes 5U and 5L for the upper flame port and the lower flame port that extend substantially parallel to the side from the burner body 1. And the air-fuel mixture from the mixing pipe 5L for the lower flame port is supplied to the lower flame port 4L through the lower flame port air-fuel mixture chamber 6L surrounded by the outer cylinder 11, the intermediate cylinder 12, and the lower burner cap 2 of the burner body 1. The air-fuel mixture from the mixing pipe 5U for the upper flame port is supplied to the upper flame port 4U through the upper flame port air-fuel mixture chamber 6U surrounded by the intermediate cylinder 12, the inner cylinder 13, the lower burner cap 2, and the upper burner cap 3 of the burner body 1.

[0013] Also, one location in the circumferential direction of the lower flame port 4L, that is, the location opposite to the extending location of the mixing pipe 5U for the upper flame port, is configured as the ignition flame port 4I. Referring to FIG. 6, the ignition flame port 4I is composed of a main ignition flame port 4Ia and auxiliary ignition flame ports 4Ib and 4Ib on both sides thereof. Further, a target portion 24 located above the main ignition flame port 4Ia is provided protruding on the outer peripheral surface of the annular wall 23 of the lower burner cap 2. An ignition electrode 7 is arranged outside the burner body 1 so as to face the target portion 24. Then, the air-fuel mixture ejected from the ignition flame port 4I, correctly speaking, the air-fuel mixture ejected from the main ignition flame port 4Ia, is ignited by the spark discharge between the ignition electrode 7 and the target portion 24, and the flame transfers to the adjacent lower flame port 4L through the auxiliary ignition flame port 4Ib.

[0014] In addition, the upper burner cap 3 is provided with a visor portion 33 that protrudes radially outward at a position above the ignition electrode 7 so that the visor portion 33 can prevent the ignition electrode 7 from being splashed. Further, a thermocouple 8 for flame detection is arranged outside the burner body 1, slightly separated from the ignition electrode 7 in the circumferential direction.

[0015] Incidentally, in the air-fuel mixture chamber 6L for the lower flame port, the air-fuel mixture flows in at a location circumferentially separated from the ignition flame port 4I, with a motion component in a direction inclined with respect to the radial direction passing through that location (the longitudinal direction of the mixing pipe 5L for the lower flame port). Therefore, the air-fuel mixture may swirl in the air-fuel mixture chamber 6L for the lower flame port and flow into the ignition flame port 4I with a swirling component. When the air-fuel mixture flows into the ignition flame port 4I with a swirling component, the air-fuel mixture is ejected from the ignition flame port 4I in a direction inclined circumferentially, and the ejection flow of the air-fuel mixture deviates from the discharge gap between the ignition electrode 7 and the target portion 24, making it easy to cause ignition failure.

[0016] Therefore, in the present embodiment, a pair of ribs 25, 25 that are longitudinally long in the vertical direction and protrude from the cylindrical portion 21 on the inner peripheral portion of the lower burner cap 2 and are close to the outer cylindrical portion 11 of the burner body 1 are provided at two circumferential locations separated from each other in the circumferential direction so as to sandwich the ignition flame port 4I in the lower air-fuel mixture chamber 6L. Note that the outer cylindrical portion 11 is provided with a cylindrical hanging edge portion 11b that hangs down from the inner peripheral edge of the inner bent flange portion 11a at the upper end. And as shown in FIG. 5, each rib 25 is close to this cylindrical hanging edge portion 11b. Also, the upper part of each rib 25 reaches the lower surface of the lower burner cap 2 and the inner peripheral surface of the annular wall 22, but it may not reach the lower surface of the lower burner cap 2 or the inner peripheral surface of the annular wall 22, and there may be a slight gap between them. Further, in the present embodiment, the circumferential positions of the circumferential inner side surfaces of the ribs 25 and the circumferential outer side surface of the ignition flame port 4I (specifically, the circumferential outer side surface of the sub-ignition flame port 4Ib) match, but the position of the circumferential inner side surface of each rib 25 may be slightly shifted outward in the circumferential direction from the circumferential outer side surface of the ignition flame port 4I.

[0017] If the pair of ribs 25, 25 are provided as described above, after the air-fuel mixture flows upward from below between the pair of ribs 25, 25 with the swirling component removed, it flows into the ignition flame port 4I, and the air-fuel mixture is ejected from the ignition flame port 4I in the radial direction without tilting circumferentially. As a result, the ejection flow of the air-fuel mixture from the ignition flame port 4I does not deviate from the discharge gap between the ignition electrode 7 and the target portion 24, and the ignition performance is improved.

[0018] As described above, the embodiments of the present invention have been described with reference to the drawings, but the present invention is not limited thereto. For example, in the above embodiment, each rib 25 is close to the cylindrical hanging edge portion 11b which is the outer cylindrical body 11 of the burner body 1, but it is also possible to bring each rib 25 into contact with the cylindrical hanging edge portion 11b. Further, in the above embodiment, the burner body 1 is made of sheet metal, but at least the outer cylindrical body 11 of the burner body 1 is made of casting, and a pair of ribs protruding from the outer cylindrical body 11 and contacting or approaching the cylindrical portion 21 of the inner peripheral portion of the lower burner cap 2 are provided at two circumferential positions separated in the circumferential direction so as to sandwich the ignition flame port 4I.

Explanation of Signs

[0019] 1…Burner body, 11…Outer cylindrical body, 12…Intermediate cylindrical body, 13…Inner cylindrical body, 2…Lower burner cap, 21…Cylindrical portion, 24…Target portion, 25…Rib, 3…Upper burner cap, 31…Cylindrical portion, 4L…Lower stage flame port, 4U…Upper stage flame port, 4I…Ignition flame port, 6L…Mixture chamber for lower stage flame port, 6U…Mixture chamber for upper stage flame port, 7…Ignition electrode.

Claims

【Claim 1】 A burner for a stove having upper and lower two-stage flame ports, comprising a burner body having an inner, middle, and outer triple cylinder structure, an annular lower burner cap having a cylindrical portion vertically provided on its inner circumference and fitting into the middle cylinder of the burner body, and defining a number of lower-stage flame ports with a circumferential gap between the outer cylinder of the burner body, and an annular upper burner cap having a cylindrical portion vertically provided on its inner circumference and fitting into the inner cylinder of the burner body, and defining a number of upper-stage flame ports with a circumferential gap between the lower burner cap. The mixture is supplied to the lower-stage flame ports through a lower-stage mixture chamber surrounded by the outer cylinder, the middle cylinder, and the lower burner cap of the burner body, and the mixture is supplied to the upper-stage flame ports through an upper-stage mixture chamber surrounded by the middle cylinder, the inner cylinder, the lower burner cap, and the upper burner cap of the burner body. One of the lower-stage flame ports located at one circumferential position is configured as an ignition flame port, and a target portion is provided on the lower burner cap above the ignition flame port. The mixture ejected from the ignition flame port is ignited by a spark discharge between the ignition electrode arranged to face the target portion and the target portion. A burner for a stove, characterized in that a pair of longitudinally long ribs projecting from one of the cylindrical portion of the inner circumference of the lower burner cap and the outer cylinder of the burner body and abutting or approaching the other are provided at two circumferential positions separated in the circumferential direction so as to sandwich the ignition flame port in the lower-stage mixture chamber.

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