Abstract: A gap measurement device for measuring a gap between an upper plate and a lower plate in a material formed of the upper plate and the lower plate that overlap with each other in the Z-axis direction, which is the thickness direction. The gap measurement device has an ultrasonic sensor that functions as a plate thickness measurement sensor for measuring a plate thickness that is the thickness of the upper plate, a laser sensor that functions as a step measurement sensor for measuring a step that is the distance between the upper surface of the upper plate and the upper surface of the lower plate, and a calculation unit for calculating the gap between the upper plate and lower plate by subtracting the plate thickness from the step.

Abstract: A gap measurement device for measuring a gap between an upper plate and a lower plate in a material formed of the upper plate and the lower plate that overlap with each other in the Z-axis direction, which is the thickness direction. The gap measurement device has an ultrasonic sensor that functions as a plate thickness measurement sensor for measuring a plate thickness that is the thickness of the upper plate, a laser sensor that functions as a step measurement sensor for measuring a step that is the distance between the upper surface of the upper plate and the upper surface of the lower plate, and a calculation unit for calculating the gap between the upper plate and lower plate by subtracting the plate thickness from the step.

Abstract: A gap measuring device is provided with: a translucent member which is formed from a translucent material and has a first abutting surface which abuts an upper surface of a lower plate, and a second abutting surface which is provided perpendicular to the first abutting surface and abuts a side end surface of an upper plate; an image-capturing unit which captures an image of a gap, through the translucent member; and a gap measuring unit which measures the gap on the basis of image information relating to the gap of which an image has been captured. The translucent member is provided, at an edge portion between the first abutting surface and the second abutting surface, with a mark indicating the position of the edge portion.

Abstract: Provided is a hot-water heater manufacturing method capable of obtaining stable heat exchange characteristics by applying a moderate contact surface pressure between heating-medium circulating tubes and heater members that constitute a hot-water heater, and capable of improving the reliability by enhancing the joint strength between the heating-medium circulating tubes, with a simple and easy manufacturing process.

Abstract: A heat exchanger comprises: a pair of headers (10, 10) which are provided in parallel facing each other through a predetermined distance and a pathway of the fluid is respectively provided therein; and a plurality of flat heat-exchange tubes (20, 20 . . . ) which are provided between the headers in parallel, both ends thereof are fastened to the headers, and a pathway of the refrigerant for connecting the pathways of both headers is respectively provided therein. In this heat exchanger, the heat-exchange tubes and the headers are air-tightly and liquid-tightly fastened by inserting end portions (21, 21 . . . ) of the heat-exchange tubes into insertion holes (11, 11 . . . ) which are bored on the headers. Furthermore, in the vicinity of opening ends (29) of both end portions of the flat heat-exchange tubes, shape-holding portions (41) for preventing deformation of the opening ends are provided.