A multiple valve assembly for controlling water loss during leak using pressure difference between two passages

摘要

A valve assembly (10) for reducing water loss from a leak from a water device (50) is disclosed. The valve assembly (10) includes a first passage (20) through which water flows from a water source to the water device (50) and a second passage (40) through which water flows from the water device. A first valve (15) is in fluid communication with the first passage (20) and the second passage. The first valve (15) is operable for obstructing the first passage (20) in response to a change in pressure differential between water in the first passage (20) and water in the second passage (40) resulting from a leak of water from the water device (50). The valve assembly (10) also includes a second valve (30) in fluid communication with the first passage (20). The second valve (30) is responsive to the obstruction of the first passage (20) to close the first passage (20) and thereby stop water from flowing from the water source to the water device (50).