Vacuum compensation valve
Patent 5566421 Issued on October 22, 1996. Estimated Expiration Date: 
September 26, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 26, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3343197 3443274 Portable tacking system Dust collection apparatus Industrial central-vacuum system Patent #: 4991253 InventorApplicationNo. 530101 filed on 09/26/1995US Classes:15/314, With flexible conduit connection between ambulant air draft applying means and relatively stationary air pump or supply15/319With automatic controlExaminersPrimary: Moore, Chris K.Attorney, Agent or FirmForeign Patent References
International ClassA47L 009/00Foreign Application Priority Data1993-03-26 GBAbstractApparatus for vacuum collection of material, where a vacuum source is used for creating a vacuum to draw air into a displacement chamber, and at least two hoses are connected to the displacement chamber for vacuum collection of materials from various locations. Pressure sensors are connected to sense pressure in each hose, dampers are operable in response to the relative pressures between the hoses so as to vary the effective area of the respective connections between the hoses and the displacement chamber in order to equalize and optimize the relative pressures, and an automatic control such as a programmable logic controller is employed to operate the dampers in response to said sensed pressures. | |
