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Class Information
Number: 137/389
Name: Fluid handling > Liquid level responsive or maintaining systems > With second diverse control
Description: Apparatus wherein the level responding or maintaining flow is increased or diminished by an external means or in response to a change in condition other than liquid level, either by a means acting upon the liquid level responsive control means or by a second means in series or parallel therewith.

Sub-classes under this class:

Class Number Class Name Patents
137/390 Manual control 41

Patents under this class:
1 2

Patent Number Title Of Patent Date Issued
8607730 Method of replacing liquid of circulation line in substrate liquid processing apparatus of single-wafer type Dec. 17, 2013
8534313 Toilet fill valve auxiliary shutoff mechanism Sep. 17, 2013
8479763 Electronic venting and mechanical roll over valve Jul. 9, 2013
8166996 Toilet bowl overflow prevention and water conservation system and method May. 1, 2012
7931041 System and method for controlling liquid level in a vessel Apr. 26, 2011
7849890 Apparatus for and methods of draining an enclosure Dec. 14, 2010
7757708 Toilet bowl overflow prevention and water conservation system and method Jul. 20, 2010
7726584 Thermal valve assembly Jun. 1, 2010
7509973 System to prevent excess fluid flow with a secondary resetting shut-off valve assembly Mar. 31, 2009
7503082 Air massage system for bathtub Mar. 17, 2009
7055546 Fluid intake pressure regulating system Jun. 6, 2006
7032257 Flush tank having electromagnetic controler Apr. 25, 2006
6994107 Easy-to-install, mechanically-operated automatic/manual device for controlling an outlet for water or any fluid Feb. 7, 2006
6026837 Automated chemical drain system Feb. 22, 2000
5992447 Device for filling vinyl lined pools Nov. 30, 1999
5814213 Skimming apparatus Sep. 29, 1998
5626162 Water control gauge May. 6, 1997
5557939 Control system for absorption chillers Sep. 24, 1996
5460197 Valve for a tap of a gas cylinder and tap having such a valve Oct. 24, 1995
5351712 Hot water recovery system Oct. 4, 1994
5197569 Constant depth reservoir Mar. 30, 1993
5178009 Integral temperature and liquid level sensor and control Jan. 12, 1993
5012838 Solenoid valve incorporating liquid surface detecting valve May. 7, 1991
4811754 Rinse water valve for vacuum toilet system Mar. 14, 1989
4802334 Augmentor fuel system Feb. 7, 1989
4702271 Flow-control device Oct. 27, 1987
4686086 Process system including fluid flow control apparatus Aug. 11, 1987
4592098 Liquid level control system Jun. 3, 1986
4549570 Waste disposal monitoring system Oct. 29, 1985
4538307 Flood level sensor for fluid filling systems Sep. 3, 1985
4510967 Anti-backflow valve for therapy tubs and the like Apr. 16, 1985
4498203 Flood preventer for fluid filling systems Feb. 12, 1985
4495028 Process control for flash concentrating solutions containing polyolefins Jan. 22, 1985
4493350 Device for removing air from hermetic, automatically emptying centrifuge drums Jan. 15, 1985
4469117 Valve device for the prevention of the overfilling of portable containers, particularly gas cylinders Sep. 4, 1984
4469116 Valve device for the prevention of the overfilling of portable containers, particulary gas cylinders Sep. 4, 1984
4462417 Valve assembly Jul. 31, 1984
4421459 Fluid level control apparatus Dec. 20, 1983
4406299 Liquid level valve Sep. 27, 1983
4386623 Nonlinear control of liquid level Jun. 7, 1983
4359432 Post-mix beverage dispensing system syrup package, valving system, and carbonator therefor Nov. 16, 1982
4316484 Liquid level valve Feb. 23, 1982
4268461 Temperature compensating float arm for use in carburetors May. 19, 1981
4265263 Non-linear level controller May. 5, 1981
4217926 Thermally controlled oil storage reservoir for a transmission Aug. 19, 1980
4178957 Dishwasher fill system Dec. 18, 1979
4161957 Leakage protective apparatus for storage containers or the like Jul. 24, 1979
4151854 Method and apparatus for mixing and supplying fountain solution to printing presses May. 1, 1979
4148334 Liquid level control sytem Apr. 10, 1979
4132242 Chemical distribution system Jan. 2, 1979

1 2

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