Abstract: A fuel tank includes metal-made upper and lower tank half bodies respectively having, on respective outer peripheries thereof, an upper joint flange and a lower joint flange joined thereto. The lower tank half body includes: a lower tank main body portion that is elongated in a direction parallel to a reference plane including joint surfaces of lower and upper planar flange portions as parts of the lower and upper joint flanges, respectively, includes, along a longitudinal direction thereof, a narrow portion narrower on one side than the other side, and bulges toward a lower side from the reference plane; and a pair of expansion tank portions that are disposed on opposite sides of the narrow portion as seen in a plan view from a direction orthogonal to the reference plane, formed to be shallower than the lower tank main body portion, and bulge downward from the reference plane.

Abstract: In a fuel tank in which an upper joint flange of an upper tank half body and a lower joint flange of a lower tank half body are sandwiched between and seam welded by a pair of roller electrodes, the lower tank half body includes a lower tank main body portion and expansion tank portions shallower than the lower tank main body portion and disposed on opposite sides of the lower tank main body portion. A side wall of at least one of the upper and lower tank half bodies is provided with roller escape recesses recessed inwardly, the roller escape recesses being formed at a position corresponding to a connection portion of a main body corresponding joint portion and expansion tank corresponding joint portions in a joint portion formed by seam welding, and avoiding a contact with at least one of the pair of roller electrodes.

Abstract: An upper half body flange is disposed over a whole circumference of a lower end portion of an upper half body along a plane and a lower half body flange is disposed over a whole circumference of an upper end portion of a lower half body along the plane. The upper half body and the lower half body are made of titanium material, and the upper half body flange and the lower half body flange have linear outer edges as straight line portions. The upper half body has a side surface, the lower half body has a side surface, and the side surface and the side surface include recesses and convex portions. The recesses and the convex portions are disposed within a range of lengths of the straight line portions when viewed from above in the direction perpendicular to the plane.

Abstract: In a fuel tank in which an upper joint flange of an upper tank half body and a lower joint flange of a lower tank half body are sandwiched between and seam welded by a pair of roller electrodes, the lower tank half body includes a lower tank main body portion and expansion tank portions shallower than the lower tank main body portion and disposed on opposite sides of the lower tank main body portion. A side wall of at least one of the upper and lower tank half bodies is provided with roller escape recesses recessed inwardly, the roller escape recesses being formed at a position corresponding to a connection portion of a main body corresponding joint portion and expansion tank corresponding joint portions in a joint portion formed by seam welding, and avoiding a contact with at least one of the pair of roller electrodes.

Abstract: A fuel tank includes metal-made upper and lower tank half bodies respectively having, on respective outer peripheries thereof, an upper joint flange and a lower joint flange joined thereto. The lower tank half body includes: a lower tank main body portion that is elongated in a direction parallel to a reference plane including joint surfaces of lower and upper planar flange portions as parts of the lower and upper joint flanges, respectively, includes, along a longitudinal direction thereof, a narrow portion narrower on one side than the other side, and bulges toward a lower side from the reference plane; and a pair of expansion tank portions that are disposed on opposite sides of the narrow portion as seen in a plan view from a direction orthogonal to the reference plane, formed to be shallower than the lower tank main body portion, and bulge downward from the reference plane.

Abstract: An upper half body flange is disposed over a whole circumference of a lower end portion of an upper half body along a plane and a lower half body flange is disposed over a whole circumference of an upper end portion of a lower half body along the plane. The upper half body and the lower half body are made of titanium material, and the upper half body flange and the lower half body flange have linear outer edges as straight line portions. The upper half body has a side surface, the lower half body has a side surface, and the side surface and the side surface include recesses and convex portions. The recesses and the convex portions are disposed within a range of lengths of the straight line portions when viewed from above in the direction perpendicular to the plane.

Abstract: A lead tone is generated on the basis of an input tone signal. Meanwhile, a specific pitch of the input tone signal is sequentially detected, from which is detected a normalized pitch corresponding to any one of the musical pitch names. Then, difference information is obtained which pertains to a difference between the specific pitch and the normalized pitch, and a pitch having a given pitch interval from the normalized pitch is determined as a target pitch of a tone signal to be generated. Then, a harmony tone is generated which has a pitch obtained by modulating the target pitch in accordance with the difference information.

Abstract: Specific pitch of an input tone signal is sequentially detected, and a normalized pitch corresponding to a pitch name is sequentially detected on the basis of the specific pitch. It is determined whether there has been a variation in the detected pitch. Lead tone (first tone signal) is generated on the basis of the input tone signal, and a harmony tone (second tone signal) is generated on the basis of the detected pitch. When it is determined that there has been a variation in the pitch, processing waits until a predetermined time passes, and control is performed to change a pitch of the second tone signal if a pitch detected immediately before the variation and a current detected pitch are determined to be different from each other upon the passage of the predetermined time.

Abstract: A lead tone is generated on the basis of an input tone signal. Meanwhile, a specific pitch of the input tone signal is sequentially detected, from which is detected a normalized pitch corresponding to any one of the musical pitch names. Then, difference information is obtained which pertains to a difference between the specific pitch and the normalized pitch, and a pitch having a given pitch interval from the normalized pitch is determined as a target pitch of a tone signal to be generated. Then, a harmony tone is generated which has a pitch obtained by modulating the target pitch in accordance with the difference information.

Abstract: Specific pitch of an input tone signal is sequentially detected, and a normalized pitch corresponding to a pitch name is sequentially detected on the basis of the specific pitch. It is determined whether there has been a variation in the detected pitch. Leading tone (first tone signal) is generated on the basis of the input tone signal, and a harmony tone (second tone signal) is generated on the basis of the detected pitch. When it is determined that there has been a variation in the pitch, processing waits until a predetermined time passes, and control is performed to change a pitch of the second tone signal if a pitch detected immediately before the variation and a current detected pitch are determined to be different from each other upon the passage of the predetermined time.