The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 12, 1989
Filed:
Sep. 14, 1987
Erich J Kocher, Milwaukee, WI (US);
Vilter Manufacturing Corporation, Milwaukee, WI (US);
Abstract
A liquid level control in a refrigeration system operates a solenoid valve to maintain the level of liquid refrigerant in a vessel within a range defined by predetermined lower and upper liquid levels, sounds an alarm if the upper level is exceeded and stops a pump if the lower level is violated. The control comprises a float assembly and a switching assembly. The float assembly comprises a float chamber connected to the vessel, a float ball therein, a vertically extending float rod connected to the float ball and movable along a vertical path, and a pair of spaced apart stop members on the float rod disposed within the switching assembly. The switching assembly comprises a switch actuator permanent magnet, having magnet poles at opposite ends, slidably mounted on the float rod between the stop members and movable thereby along the said path. The switch assembly also comprises three switch units which are mounted so as to be vertically spaced apart from each other and adjacent the vertical path of travel of the switch actuator magnet on the float rod. The first switch unit controls a relay for operating a solenoid valve which controls liquid flow into the vessel. The second switch unit controls a relay for operating a pump which controls liquid flow out of the vessel. The third switch unit controls a relay for operating an alarm to warn of high liquid level. Each switch unit comprises a snap-acting micro-switch actuatable between two conditions (open/close), a movable lever arm for actuating the micro-switch and movable toward and away from the vertical path of travel of the actuator magnet, and a permanent switch magnet mounted on the lever arm with one magnetic pole adjacent the path. The said one magnetic pole of the switch magnet is repelled or attracted by a pole of the actuator magnet moving therepast in response to movement of the float ball and float rod to effect snap-acting operation of the switch and operation of the appropriate relay and associated electrical device.