Patent attributes
A height adjustable seat tube includes an outer tube and an inner tube is inserted into the outer tube. An end cap is fixed to the inner tube and a valve unit in the inner tube extends through the end cap and co-movable linearly with the inner tube. An inlet valve is connected to the inner tube. An oil tube is connected between the inlet valve and the valve unit. A first oil room is defined between the oil tube and the valve unit. An oil storage member is connected between a connection member and the end cap. A first air room is defined between the inlet valve, the oil storage member and the inner tube. A second oil room is defined between the oil tube, the oil storage member and the end cap. An oil path is in communication between the first and second oil rooms.