Abstract: A steering mechanism for a push-and-pull vehicle provides a handlebar to be used to steer a vehicle left and right while simultaneously being used to drive the vehicle forward by pushing and pulling action. The handlebar is at the top of a swing pole, the swing pole being held by a turning sleeve on a swing arm pivoted on the vehicle frame. The swing pole connects the handlebar to a frame supported u-joint which is connected to a vehicle steering mechanism. The turning sleeve connects the handlebar and swing pole to the swing arm, the output of the swing arm driving the vehicle forward.

Abstract: This invention A Push and Pull Vehicle by Stand-and-Sit Action provides a solid turning, fast reaction steering feeling as a regular bicycle while still able to push or to pull or do both to drive vehicle forward. It just works on opposite side force of pulling and pushing by stand-up and sit-down actions. It contains a handlebar with a steering column on steering, a treadle and a moving seat working together as leverage against each other, and with an increasing ratio device to magnify driving stroke and drives 2 one-way devices on rear wheel at a continuous cycle.

Abstract: A Steering Mechanism for a Push and Pull Vehicle is to provide a solid turning, fast reaction steering feeling as a regular bicycle steering function, by handlebar turning left or right while still be able to use pulling or pushing action to power a vehicle forward. It contains handlebar at top of swing pole, a turning sleeve on a swing arm to hold swing pole, a frame supported U-joint bearing holds a U-joint which steer vehicle direction, and said swing arm contains a pivot support on vehicle frame and output to drive vehicle forward. So said handlebar is able to swing back and forth on swing arm pivot support to drive vehicle forward and turn left and right on said turning sleeve for steering directions.

Abstract: The Swing Powered Scooter is to provide a transportation powered by hands instead of by feet. It has a handlebar on top of a swing pole, with a center point which is supported by an inner ring of a bearing on a board; Using pulling or pushing action drives wheels move, at same time, the handlebar steers in the forward direction. The bottom of the swing pole drives an increasing gear ratio mechanism; and by positioning an idler gear to change speeds or by 2 chains. Furthermore using a rack and a passive gear makes this invention is able to use pushing or pulling or both actions to make vehicle move forward.

Abstract: All tip retractable pens have no caps to cover their pen tips, instead their pen tips or tip protection covers are retractable such as mechanical ball pens, twisted ball pens or telescopic ball pens. Theirs pen tips will be same direction to theirs clips, and always point to ground either in writing or any time unused. Because theirs structure as retractable pen, they don't need caps. To make retractable pen be able to use liquid ink, this invention use spool valves inside the liquid ink cartridge, which also applies on the pen tip is same direction with its pen clip or has no cap to cover its pen tip. Using an air valve, a pen tip valve, a valve rod, and a pushing or twist action to change valves result as unused state: the pen tip valve close ink path and the air valve opens to vent expansion air. And as writing state: the air valve closed to create a vacuum to hold ink in tube and the pen tip valve open the ink to pen tips and air vents through an outlet at top of valve rod to balance pressure.