Abstract: A foldable luggage carrier includes a frame, a supporting tray and a pair of wheeled carriages. The tray has a pair of pivot brackets pivotally connected to two leg portions of the frame such that the tray is pivotable between a forwardly extended position and a fold-up position. Each of the pivot brackets includes a pair of opposed plates and a cam portion at a corner. Each of the wheeled carriages includes a wheel bracket having a sleeve bearing rotatably supported on the leg portions of the frame to permit the wheeled carriages to pivot between rearwardly extended positions and folded-in positions. The sleeve bearing has a guiding slope section at a bottom to interact with each cam portion of the pivot bracket in a manner such that the wheeled carriages automatically pivot to the folded-in positions and the rearwardly extended positions when the tray is moved between the fold-up position and the forwardly extended position.

Abstract: A foldable platform truck includes a platform, two wheel-connecting bars rotatably attached to the platform, a handle assembly, a handle release and locking mechanism for controlling the handle assembly, a pair of first gear members and a pair of second gear members. The handle release and locking mechanism has an actuator to be operated to allow the handle assembly to pivot between an upright position and a horizontal position. When the handle assembly is in the horizontal position, the wheels are folded up underneath the platform and lie horizontally with respect thereto. And, when the handle assembly is pulled away from the platform to the upright position, the first gear members engage and turn the second gear members, resulting in the wheel-connecting bars rotating to fold out the wheels from underneath the platform toward an eventual perpendicular position with respect to the underside of the platform.

Abstract: A foldable platform truck includes a platform, two wheel-connecting bars rotatably attached to the platform, a handle assembly, a handle release and locking mechanism for controlling the handle assembly, a pair of first gear members and a pair of second gear members. The handle release and locking mechanism has an actuator to be operated to allow the handle assembly to pivot between an upright position and a horizontal position. When the handle assembly is in the horizontal position, the wheels are folded up underneath the platform and lie horizontally with respect thereto. And, when the handle assembly is pulled away from the platform to the upright position, the first gear members engage and turn the second gear members, resulting in the wheel-connecting bars rotating to fold out the wheels from underneath the platform toward an eventual perpendicular position with respect to the underside of the platform.