Abstract: A tube spacer S formed by bending a wire, includes a plurality of projections 20 and a base-bending portion 21. Each of the projections 20 is inserted between tubes, and has a pair of extending portions 201 extend in X direction and a front-bending portion 202 for connecting both front ends of the pair of extending portions 201. The base-bending portion 21 connects both rear ends of the projections 20 so that the projections 20 are arranged at interval in Z direction. With this structure, manufacturing cost for the tube spacer S can be low, and the tubes can be stably supported.

Abstract: A tube spacer S formed by bending a wire, includes a plurality of projections 20 and a base-bending portion 21. Each of the projections 20 is inserted between tubes, and has a pair of extending portions 201 extend in X direction and a front-bending portion 202 for connecting both front ends of the pair of extending portions 201. The base-bending portion 21 connects both rear ends of the projections 20 so that the projections 20 are arranged at interval in Z direction. With this structure, manufacturing cost for the tube spacer S can be low, and the tubes can be stably supported.

Abstract: A combustion apparatus (1) is generally composed of a principal part (5), a supplementary part (6) and a burner port assembly (3). Four metal plates (7,8,10,11) constituting the principal and supplementary parts (5,6) are pressed to have in them several protuberances and recesses. These metal plates are laid one on another to form in them some hollow spaces and sealed regions. These hollow spaces communicate with each other to form a thin gas passage (22) together with a thick gas passage (73) in this combustion apparatus (1) in such a manner that its condition of thick and thin fuel combustion is rendered more stable.

Abstract: A combustion apparatus (1) with a burner port assembly (3) comprises an elongated first array of main burner ports (53) for jetting and burning a fuel gas mixture of a concentration to make main flames. The combustion apparatus (1) comprises at least one second arrays of auxiliary burner ports (63) for jetting and burning a further fuel gas mixture of a different concentration to make auxiliary flames, wherein the second arrays of said auxiliary burner ports (63) extend along the first array of said main burner ports (53). The burner port assembly (3) is constructed using inner and outer wall segments (52) together with outermost wall segments (52a,52f) or bands (58). One of the bands (58) faces the corresponding one of said outermost segments (52a,52f) so as to define between them collateral burner ports (61a,61b).

Abstract: A combustion apparatus (1) is generally composed of principal part (5), a supplementary part (6) and a burner port assembly (3). Four metal plates (7,8,10,11) constituting the principal and supplementary parts (5,6) are pressed to have in them several protuberances and recesses. These metal plates are laid one on another to form in them some hollow spaces and sealed regions. These hollow spaces communicate with each other to form a thin gas passage (22) together with a thick gas passage (73) in this combustion apparatus (1) in such a manner that its condition of thick and thin fuel combustion is rendered more stable.

Abstract: A combustion apparatus (1) with a burner port assembly (3) comprises an elongated first array of main burner ports (53) for jetting and burning a fuel gas mixture of a concentration to make main flames. The combustion apparatus (1) comprises at least one second arrays of auxiliary burner ports (63) for jetting and burning a further fuel gas mixture of a different concentration to make auxiliary flames, wherein the second arrays of said auxiliary burner ports (63) extend along the first array of said main burner ports (53). The burner port assembly (3) is constructed using inner and outer wall segments (52) together with outermost wall segments (52a,52f) or bands (58). One of the bands (58) faces the corresponding one of said outermost segments (52a,52f) so as to define between them collateral burner ports (61a,61b).