Mass flow controller
Patent 5159951 Issued on November 3, 1992. Estimated Expiration Date: 
October 15, 2011. 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.
October 15, 2011. 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 3730215 3732889 Valve assembly for pressurized fluid systems Mass flow controller Patent #: 4921005 InventorsAssigneeApplicationNo. 776026 filed on 10/15/1991US Classes:137/486, Responsive to change in rate of fluid flow137/487.5, Electrically actuated valve251/282ReciprocatingExaminersPrimary: Cohan, AlanAttorney, Agent or FirmInternational ClassG05D 007/06Foreign Application Priority Data1989-09-26 JPAbstractA mass flow controller having a bypass portion provided in a body through which a large amount of gas is passed and a sensor portion, laid between a primary chamber which is an inlet of the bypass portion and a secondary chamber which is an outlet of the bypass portion, through which gas flows at a small flow rate proportional to the flow rate of the gas passed through the bypass portion and capable of measuring the total flow rate of gas by measuring the flow rate in the sensor portion. The body is partitioned by a bulkhead into a primary chamber and a secondary chamber. The primary chamber is provided with an inlet for gas inflow and the secondary chamber is provided with an outlet for gas outflow. The bulkhead is provided with a plurality of through holes for connecting the primary chamber to the secondary chamber, and bypass elements selected depending on the flow rate in the bypass portion are fitted in the through holes in the bulkhead. Expansion plugs are fitted in the through holes in which no bypass elements are fitted not to cause gas to flow. | |
