Patent ID: 7798171
Filing Date: 2010-09-21
Classification: A01K,Y10T

Abstract:
1. A valve assembly comprising: a first assembly connected to an exhaust system constructed and arranged to withdraw air through the first assembly, the first assembly having a first displaceable member having a first open position and a first closed position, the first assembly constructed and arranged to mount to the exhaust system, wherein a first pressure is required to move the first displaceable member from the first closed position to the first open position; a second assembly having a second displaceable member having a second open position and a second closed position, wherein a second pressure greater than the first pressure is required to move the second displaceable member from the second closed position to the second open position; wherein the second assembly is removable from the first assembly, wherein the first displaceable member is in the first closed position and the second displaceable member is in the second closed position when the first assembly and the second assembly are separated; wherein the second assembly is constructed and arranged to displace the first displaceable member when the second assembly is connected to the first assembly; wherein the second assembly and the first assembly are connected to define an area therebetween; wherein the valve assembly has a first connected position wherein the first assembly and the second assembly are connected such that a seal is created between the first and the second assembly wherein the first displaceable member is in the first closed position and the second displaceable member is in the second closed position to prevent leakage of contamination from the valve assembly into the atmosphere; the valve assembly having a second connected position wherein the first displaceable member is in the first open position and the second displaceable member is in the second closed position, so that air from within the area between the first assembly and the second assembly is withdrawn through the first assembly; the valve assembly having a third connected position wherein the first displaceable member is in the first open position and the second displaceable member is in the second open position; wherein the second assembly is displaced toward the first assembly as the valve assembly transitions from the first connected state to the second connected state, the second assembly being displaced further toward the first assembly as the valve assembly transitions from the second connected state to the third connected state to further prevent leakage of contamination from the valve assembly, wherein the first displaceable member comprises a projection constructed and designed to contact the second displaceable member when the first assembly and the second assembly are connected.