NORITZ CORPORATION

A heat exchanger includes: a case which has a first side wall that stands upright in a vertical height direction and to which a heating medium is supplied inside; and heat transfer tubes for heating hot water housed in the case. Two end portions of the heat transfer tubes in a longitudinal direction are joined to the first side wall via brazing portions, and the heat transfer tubes are supported by the first side wall. The heat exchanger further includes heat transfer tube support portions provided on the first side wall for supporting portions of the heat transfer tubes near the first side wall to prevent the portions of the heat transfer tubes near the first side wall from descending below a first predetermined height.

Provided is a water heater including a burner that receives a supply of combustion air from a fan, a heat exchanger having a heat transfer tube, and a combustion chamber case in which a combustion chamber of the burner is formed in the interior thereof and which is to be capable of guiding combustion gas generated by the burner to the heat exchanger. The water heater further includes a unit case that surrounds the combustion chamber case, and a region on the outside of the combustion chamber case within the unit case serves as an air pressure chamber having a higher pressure than the combustion chamber. Thus, combustion gas leakage to the outside can be prevented or suppressed appropriately by means of a simple configuration.

A water heating device equipped with a housing, a fan and a chamber arranged in the interior of the housing, and screws. The housing has first and second side plates which oppose one another in a first direction and extend from the ends of a back plate along a second direction intersecting the first direction. An opening part is provided in the housing on the side opposite the back plate in the second direction. The fan has a discharge opening, a first flow passage extending along the first direction, and a first flange. The chamber has an intake opening, a second flow passage extending along the first direction, and a second flange. The first and the second flanges are secured by screws. In a planar view, the center axis of the screws is slanted such that a head portion is closer to the opening part than the tip-end portion.

A heat exchanger includes a case into which heating gas is supplied, a heat transfer pipe accommodated in the case, and first and second header sections, each of which has a chamber formed using a protruding part provided in the sidewall section, and to which the heat transfer pipe is connected such that a fluid to be heated enters and exit the chamber. The sidewall section has a configuration in which an inner plate and an outer plate overlap each other, the protruding part of the first header section is provided on the inner plate and protrudes toward an inside of the case, and the protruding part of the second header section is provided on the outer plate and protrudes toward an outside of the case.

A heat exchanger includes a tube expansion portion formed by expanding a heat transfer tube so that an outer peripheral surface of the heat transfer tube is pressed against an inner peripheral surface of a hole provided in a side wall portion of a case. The tube expansion portion includes first and second bulge portions positioned respectively on the inside and the outside of the side wall portion so as to sandwich the side wall portion in an axial length direction of the heat transfer tube and configured such that respective outer peripheral surfaces thereof partially bulge outward in a radial direction of the heat transfer tube, an end portion tip end of the heat transfer tube is positioned apart from the second bulge portion, and the end portion tip end and a part in the vicinity thereof are expanded so as to be included in a part of the tube expansion portion. Thus, effects such as improving the precision with which the side wall portion of the case, the heat transfer tube, and a connecting tube are fitted to each other can be achieved, and as a result, the respective parts can be brazed easily and appropriately.

Provided is a blowing device capable of improving a noise reduction effect as compared with a conventional case, and a combustion device including the blowing device is provided. In a rear side shroud of an impeller configuring a blowing device, a first inclined surface portion that is inclined so as to be located frontward toward the radial outer side is formed in a front surface portion of the rear side shroud in a region close to the outer peripheral edge, while a second inclined surface portion that is inclined so as to be located rearward toward the radial outer side is formed in a front surface portion of the rear side shroud in a region closer to the center than the first inclined surface portion.

A heat exchanger includes a plurality of heat transfer tubes extending in a first direction and aligned in a second direction intersecting with the first direction, and a plurality of fins disposed in the first direction. The fins each include a plurality of fin main bodies aligned in the second direction, and a bridging portion connecting two adjacent ones of the fin main bodies. At least one of the fin main bodies is provided with a through hole next to the bridging portion in the second direction.

Provided are a heat exchanger capable of cooling a shell plate and having good assemblability and a hot water apparatus having the same. A primary heat exchanger includes a heat exchanging portion, a shell plate, and a shell pipe portion. The shell plate surrounds the heat exchanging portion. The shell pipe portion is for cooling the shell plate. The shell plate includes a front surface portion and a main body portion. The main body portion is installed on the front surface portion and is formed by bending one sheet of plate into a U shape. The shell pipe portion is bent in a U shape along an inner surface of the main body portion and installed on the inner surface.

A heat exchanger includes fins and a plurality of pairs of cut-and-raised parts. Each pair of the cut-and-raised parts are positioned on both left and right sides in a width direction on a downstream side in a heating gas flowing direction around an outer circumference surface of each of upstream pipe body parts and face a downstream part on the outer circumference surface with a first gap therebetween. A width between upstream end parts of each pair of the cut-and-raised parts is larger than an outer diameter of each of the upstream pipe body parts. In addition, each pair of the cut-and-raised parts are inclined such that a width between downstream end parts becomes smaller than the width between the upstream end parts. A heating gas passing part having a width narrower than a dimension therebetween is provided in a region between two adjacent upstream pipe body parts.

A hot water device includes a heat exchanger and an apparatus to which the heat exchanger is to be connected. First and second cases for the heat exchanger and the apparatus to which the heat exchanger is to be connected include first and second flange portions laid over each other and welded together. The first and second flange portions are each demarcated into a corner flange portion corresponding to one of first and second corner portions, and into a non-corner flange portion other than the corner flange portion. The non-corner flange portions protrude more to the outside of the first and second cases than the corner flange portions.