Vehicle roof structure

A vehicle roof structure comprising a roof panel, and left and right roof rails extending in a longitudinal direction of a vehicle body for supporting the roof panel,

• wherein the left and right roof rails include left and right inner rails having a closed cross section and extending in the longitudinal direction of the vehicle body to constitute part of a vehicle body frame, and left and right outer panels located outward of the left and right inner rails in a vehicle width direction,
• wherein the left and right outer panels include left and right stepped sections each extending from an upper edge of a corresponding one of the left and right outer panels downward and then inward in the vehicle width direction to form a step, and left and right upper flanges each extending from a corresponding one of the left and right stepped sections downward and then inward in the vehicle width direction to form a step,
• wherein the left and right upper flanges of the left and right outer panels are overlapped, respectively, on upper surfaces of the left and right inner rails and joined thereto,
• wherein the roof panel has left and right ends formed so as to extend downwardly toward stepped surfaces of the left and right stepped sections and overlapped on the left and right stepped surfaces, whereby left and right grooves opened upward are formed by the left and right stepped sections and the left and right ends,
• wherein the left and right ends of the roof panel are joined to the left and right stepped surfaces via adhesion sections using adhesive agent and temporarily securing sections that provide temporary affixation by welding until the adhesion sections can exhibit an adhesion force,
• wherein the temporarily securing sections are covered with filling agent layers that are formed by a filling agent filled into the left and right stepped sections,
• wherein the adhesion sections are located, at the left and right ends of the roof panel, inward of the temporarily securing sections in the vehicle width direction,
• wherein widths of the filling agent layers range in the left and right stepped sections, respectively, from left and right corners formed between the upper edges of the left and right outer panels and the left and right stepped surfaces to regions covering the temporarily securing sections, and
• wherein surfaces of the filling agent layers filled into the left and right stepped sections have a substantially curved shape gradually curved downward from nearby the upper edges of the left and right outer panels to the regions covering the temporarily securing sections.