US Patent 7694430 Locking plug system

A stopper component has upper and lower ends. The stopper component is removably positioned in a cylindrical opening. A shaft/dipstick is positioned within the stopper component. The shaft/dipstick has an upper end adjacent to the upper end of the stopper component. The shaft/dipstick has a lower end. The lower end extends beneath the lower end of the stopper component. A lock has an interior end coupled to the upper end of the shaft/dipstick. In this manner positioning the lock in a first orientation will lock the stopper component in a cylindrical opening. Also in this manner positioning the lock in a second orientation will unlock the stopper component to facilitate removal of the stopper component from a cylindrical opening.