An overflow system in the bathtub has an overflow port and has a drain pipe in connection with the overflow port. A threaded flange has a stub shoulder on one end which is fitted into a circular sleeve on the overflow port. The threaded flange has exterior threads on its outer surface and a thin diaphragm secured to the end thereof opposite to the stub shoulder. A large internally threaded nut is threadably mounted on the outer end of the threaded flange. A decorative cap is frictionally snapped into engagement with protrusions on the outer surface of the nut. The cap can be removed when needed to permit the plumber to gain access to the diaphragm to cut it open for fluid flow after the system has been tested for leaks, or put in place after the cut takes place.

A flush water volume regulator is provided, capable of canceling the buoyancy force acting on a water reservoir, wherein flush water in the water reservoir can be circulated with flush water in a flush water tank outside the water reservoir. The flush water volume regulator of the present invention has a water reservoir capable of holding a predetermined amount of flush water, having a water reservoir in which an opening is formed through which flush water inside water reservoir and flush water outside water reservoir can flow, and a float prevention means for causing a force to act on water reservoir in the opposite direction to the buoyancy force produced by flush water on water reservoir in flush water tank when water supply apparatus is supplying water into flush water tank.

A flush water volume regulator is provided, capable of canceling the buoyancy force acting on a water reservoir, wherein flush water in the water reservoir can be circulated with flush water in a flush water tank outside the water reservoir. The flush water volume regulator of the present invention has a water reservoir capable of holding a predetermined amount of flush water, having a water reservoir in which an opening is formed through which flush water inside water reservoir and flush water outside water reservoir can flow, and a float prevention means for causing a force to act on water reservoir in the opposite direction to the buoyancy force produced by flush water on water reservoir in flush water tank when water supply apparatus is supplying water into flush water tank.

A toilet tank structure is formed by a primary-secondary water tank set, a tap water inlet control valve, a secondary water tank inlet control valve and a flush control module, and the tap water inlet control valve, the secondary water tank inlet control valve and the flush control module are provided for controlling the flushing and water supply to minimize the waste of water resources effectively, so as to achieve the effects of saving water and improving functionality.

An improved flush system as described herein may comprise a reservoir with a drain opening for egress of liquids disposed in the reservoir into a surrounding toilet tank. A lock mechanism is slidably received by the reservoir so that the lock mechanism is translatable between one or more fixed positions on the reservoir. In turn, translating the lock mechanism into the reservoir at increasing depths causes a size of the drain opening to be reduced and therefore adjusted.

Flush systems for flushing an object and flush toilets are disclosed. The flush system includes a first enclosed container for storing liquid to flush the object; a second container for filling liquid from a source; and a third enclosed container at least partially below each of the first enclosed container and the second container, the third enclosed container configured to contain liquid and gas and to be in fluid communication with each of the first enclosed container and the second container, and the first enclosed container and the second container configured to be in liquid communication via the third enclosed container. The gas in the third enclosed container is configured to exert a head pressure, via one or more conduits, to the liquid in the first enclosed container to flush the object.

Flush systems for flushing an object and flush toilets are disclosed. The flush system includes a first enclosed container for storing liquid to flush the object; a second container for filling liquid from a source; and a third enclosed container at least partially below each of the first enclosed container and the second container, the third enclosed container configured to contain liquid and gas and to be in fluid communication with each of the first enclosed container and the second container, and the first enclosed container and the second container configured to be in liquid communication via the third enclosed container. The gas in the third enclosed container is configured to exert a head pressure, via one or more conduits, to the liquid in the first enclosed container to flush the object.