Liquid pump control
Patent 4505643 Issued on March 19, 1985. Estimated Expiration Date: 
March 18, 2003. 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.
March 18, 2003. 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 2981195 3867290 Time delayed shut-down circuit for recirculation pump Well pump protection system Swimming pool chemical control system Remote reset Pump protector apparatus Automatic actuator for variable speed pump Swimming pool filtering system Patent #: 4421643 InventorsAssigneeApplicationNo. 06/476813 filed on 03/18/1983US Classes:417/12, Having timer or delay means210/138, WITH TIME CONTROL210/416.2, For aquarium or swimming pool417/33, Pump stop control means requiring manual reset417/44.1, By control of electric or magnetic drive motor417/44.4Low pressure stops motor from turning on pumpExaminersPrimary: Look, Edward K.Attorney, Agent or FirmInternational ClassesE04H 4/12 (20060101)E04H 4/00 (20060101) F04B 49/06 (20060101) AbstractA circulating pump (B) pumps water between a swimming pool or other reservoir (A) and a filter or other circulated fluid receiving apparatus (C). A control circuit (D) intermittently operates the circulating pump. The operating circuit includes a first timer (32) and a cycle switch (34) which is cyclically closed to produce a pump signal for a first duration with a first periodicity. The pump signal starts a second timer (54) of a time controlled switch (52). The second timer holds the time controlled switch conductive for a preselected time period. The pump signal is conducted through a bypass switch (64), and the time actuated switch. When the pressure monitored by a pressure sensor (20) exceeds a preselected pressure, a low pressure switch (62) closes conducting the pump signal around the bypass and time controlled switches. A high pressure shutoff switch (66) conducts the pump signal to a power relay coil (72) unless a preselected high pressure is monitored. The power relay coil controls relay contacts (74) through which electric power is supplied to a pump motor (40 ). | |
