US 11,730,990 B2
Flexible dry sprinkler having a differential pressure controller
Thomas Multer, Liberty, SC (US)
Assigned to The Reliable Automatic Sprinkler Co. Inc., Liberty, SC (US)
Filed by The Reliable Automatic Sprinkler Co. Inc., Liberty, SC (US)
Filed on Jun. 8, 2021, as Appl. No. 17/341,662.
Application 17/341,662 is a continuation of application No. 15/989,316, filed on May 25, 2018, granted, now 11,083,920.
Application 15/989,316 is a continuation of application No. 13/757,148, filed on Feb. 1, 2013, granted, now 8,921,324.
Claims priority of provisional application 61/594,972, filed on Feb. 3, 2012.
Prior Publication US 2021/0290999 A1, Sep. 23, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. A62C 37/11 (2006.01); A62C 35/68 (2006.01); A62C 37/14 (2006.01); A62C 35/62 (2006.01); A62C 3/00 (2006.01); A62C 35/60 (2006.01)
CPC A62C 37/11 (2013.01) [A62C 3/004 (2013.01); A62C 35/68 (2013.01); A62C 35/60 (2013.01); A62C 35/62 (2013.01); A62C 37/14 (2013.01)] 45 Claims
OG exemplary drawing
 
1. A dry fire protection sprinkler comprising:
a flexible tube having an inlet end, an outlet end, and a valve opening, and configured to contain a pressurized fluid;
a sprinkler frame connected to the outlet end of the flexible tube, and having an outlet orifice;
an outlet seal assembly having a sealing cap and a spring washer that are configured to seal the outlet orifice of the sprinkler frame, wherein the flexible tube contains the pressurized fluid between an inlet seal assembly and the sealing cap of the outlet seal assembly;
a thermally responsive element provided between the sprinkler frame and the sealing cap of the outlet seal assembly, the thermally responsive element being configured to fail when ambient temperature reaches a predetermined temperature, and to hold the sealing cap of the outlet seal assembly in an outlet orifice until the thermally responsive element fails;
a flexible tube pressure sensor configured to measure a pressure P1 of the pressurized fluid in the flexible tube;
a control valve connected to the valve opening of the flexible tube, and configured to open and to close;
a pressurized fluid source connected to the control valve and configured to supply the pressurized fluid to the flexible tube when the control valve opens, the pressurized fluid in the pressurized fluid source being at a pressure P2;
a fluid supply pressure sensor configured to measure a pressure P3 of the pressurized fluid in the fluid supply line, the pressure P2 of the pressurized fluid in the pressurized fluid source being greater than the pressure P3 of the fluid in the supply line; and
a differential pressure controller connected to the control valve, to the flexible tube pressure sensor, and to the fluid supply pressure sensor, and, when a ratio of the pressure P1 of the pressurized fluid in the flexible tube to the pressure P3 of the fluid in the fluid supply line is less than a predetermined ratio of at least 3 to 1, the differential pressure controller sends a signal to the control valve to open, in order to allow the pressurized fluid in the pressurized fluid source at the pressure of P2 to enter the flexible tube, and, when the ratio of the pressure P1 of the pressurized fluid in the flexible tube to the pressure P3 of the fluid in the fluid supply line equals the predetermined ratio, the differential pressure controller sends a signal to the control valve to close.