Abstract: A vehicle body panel having a honeycomb sandwich structure in which a honeycomb core is sandwiched between a first and a second plate includes a subhoneycomb panel formed by adhering the first plate to one major surface of the honeycomb core beforehand. The subhoneycomb panel is pressed against the second plate which is constituted by a part of a structural panel of a vehicle body with the intermediary of an adhesive layer, the other major surface of the honeycomb core being adhered to the second plate. The connection of the subhoneycomb panel to the second plate is performed after the structural panel has been connected to a strength member of the vehicle body, e. g. after a washing stage. Such a vehicle body panel with a honeycomb sandwich structure is achievable without resorting to any substantial modification of an existing vehicle body assembly line.

Abstract: An underframe of a motor vehicle includes side sill frames extending along and at opposite sides of a floor portion of a passenger compartment, and tunnel frames extending in the same direction as and interposed between the side sill frames. Each of the side sill frames and tunnel frames has a top-open channel configuration. Front side frames are also provided with a top-open channel configuration. Straight portions of the side sill frames and tunnel frames are individually connected at their front ends to the front side frames by top-open channel-like connecting portions such that the channels of those frames are communicated to each other. The underframe having such a structure is easy to produce and provided with extreme rigidity and strength.

Abstract: Apparatus for producing honeycomb panel comprising a heating chamber isolated by a wall from outer air and a plurality of drawout trays capable of being individually inserted into and withdrawn from the heating chamber through a plurality of openings formed in the wall. Each of these drawout trays has a work accommodating chamber connected to a vacuum source, a top opening of which can be hermetically closed by a flexible sheet that can be opened and closed. Also each of the drawout trays has block plates at the front and rear ends for closing the opening in the wall at every terminal positions when inserted and withdrawn.

Abstract: A floor panel disposed between a side sill and a center tunnel of a motor vehicle is constituted by a honeycomb panel having a honeycomb core which is sandwiched between an upper plate and a lower plate. The lower plate of the floor panel is formed integrally with a sill upper panel which defines the upper surface of the side sill and/or a tunnel panel which defines the upper surface of the center tunnel.