Abstract: A welding structure includes a sheet-shaped first part to be welded; a sheet-shaped second part to be welded that is positioned with respect to the first part to be welded by engaging with the first part to be welded, to perform welding; and a first positioning portion, a second positioning portion, and a third positioning portion, at which the first and second parts to be welded engage with each other. The first to third positioning portions are each configured to restrict movement of one of the first and second parts to be welded in a positioning direction, with respect to the other, and enable movement of the one in a movable direction perpendicular to the positioning direction, with respect to the other. The movable direction of each of the first and second positioning portions is the same direction as the positioning direction of the third positioning portion.

Abstract: A welding structure includes a sheet-shaped first part to be welded; a sheet-shaped second part to be welded that is positioned with respect to the first part to be welded by engaging with the first part to be welded, to perform welding; and a first positioning portion, a second positioning portion, and a third positioning portion, at which the first and second parts to be welded engage with each other. The first to third positioning portions are each configured to restrict movement of one of the first and second parts to be welded in a positioning direction, with respect to the other, and enable movement of the one in a movable direction perpendicular to the positioning direction, with respect to the other. The movable direction of each of the first and second positioning portions is the same direction as the positioning direction of the third positioning portion.

Abstract: A hole that has two opposing sides is opened in a first part to be welded, two slits are formed in corresponding portions in a second part to be welded at positions corresponding to the hole, and a bridge portion that is made to protrude by plastic deforming a portion between the two slits is provided. A raised portion of the bridge portion of the second part to be welded is inserted into the hole of the first part to be welded, such that the two sides of the hole in the first part to be welded overlap with the two slits in the bridge portion of the second part to be welded, and the first part to be welded and the second part to be welded are welded together while the first part to be welded and the second part to be welded are engaged.