Abstract: Disclosed is a folding chassis of manually driven carrier vehicles, for example, hand trucks, carts, and strollers, capable of moving over uneven, soft or spongy surfaces and surmounting obstacles. The chassis includes a frame having a reference plane and an arm having a first axis and a second axis, said arm being attached rotatable around the first axis to said frame and configured for attaching rotatable, around the second axis, a wheel arrangement having a diameter at least equal to a half of a width of said frame. Said arm is configured to pivot between at least a first and a second positions of said wheel arrangement, wherein, in the first position, said wheel arrangement is generally perpendicular to said reference plane and wherein, in the second position, said wheel arrangement is adjacent and parallel to said reference plane.

Abstract: Disclosed is a folding chassis of manually driven carrier vehicles, for example, hand trucks, carts, and strollers, capable of moving over uneven, soft or spongy surfaces and surmounting obstacles. The chassis includes a frame having a reference plane and an arm having a first axis and a second axis, said arm being attached rotatable around the first axis to said frame and configured for attaching rotatable, around the second axis, a wheel arrangement having a diameter at least equal to a half of a width of said frame. Said arm is configured to pivot between at least a first and a second positions of said wheel arrangement, wherein, in the first position, said wheel arrangement is generally perpendicular to said reference plane and wherein, in the second position, said wheel arrangement is adjacent and parallel to said reference plane.

Abstract: Disclosed is a folding chassis of manually driven carrier vehicles, for example, hand trucks, carts, and strollers, capable of moving over uneven or spongy surfaces and surmounting obstacles. The chassis includes a frame having a first plane, an arm with an axle, and a hub having a plurality of wheels. The arm is rotatably attached to the frame with the hub rotatably disposed onto the axle and each of the plurality of wheels is rotatably attached to said hub around an axis parallel to said axle. The arm is configured to pivot between at least positions of the hub been generally perpendicular to said first plane and the hub been juxtaposed to said first plane.