Abstract: An operation arm built on one side or a plurality of sides of a hand cart provided with a wheel, includes an operation section touched by an operator, and a support extending from the operation section to the hand cart, and supporting the operation section against the hand cart, and also includes a rear inclined portion inclined from an upper end of the support toward the rear side at a predetermined angle, and a grip continuous with the rear inclined portion, extending in directions crossing the forward direction and the backward direction, an extension of the grip inclined to the front side with respect to the support and formed into a circular arc shape. By so constituting, a manual pushing force is efficiently transmitted to the hand cart and an operator can operate the operation arm in a comfortable posture.

Abstract: A trailer having front and rear pairs of wheels, each wheel being rotatably supported on a knuckle arm having a pivotal shaft tilted inwardly for biasing the wheel to a straight line position, a front tow bar pivotally mounted on a front steering member pivotally secured to the trailer body, a rear steering member pivotally mounted on a rear portion of the trailer body, a pair of tie rods connecting the knuckle arms of the front wheels and the front tow bar and a pair of rear tie rods connecting the knuckle arms of the rear wheels and the rear steering member, a rear stabilizer rear stabilizer having a spring for urging the rear steering member straight ahead between the rear steering member and the trailer body and a front stabilizer between the front tow bar and the body.

Abstract: A cart having a frame, front and rear wheels, and a handle. A pair of elevating link mechanisms are mounted on the frame, each comprising a pair of arms pivotally connected to each other at intermediate positions thereof, rollers are provided on both ends of each of the arms, lower rollers are mounted on rails provided on the frame. A carrier is engaged with upper rollers of the link mechanisms by guide rails. A hydraulic jack is vertically provided on the frame, a ram of the jack engages with a ram receiver supported on two corresponding arms at lower portions thereof and rotatable about lateral axis. A pump is provided for supplying liquid to said hydraulic jack. The elevating link mechanisms are extended by projecting the ram of the jack for elevating the carrier.