# US 2019/0170047 A1 · Stop valve, scr system, and method for detecting leaks and/or identifying variations in metered amounts > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170047 A1 - Document ID: US20190170047A1 - Status: Published application - Kind: A1 - Application number: 16/302,250 - Filed: 2017-03-24 - Published: 2019-06-06 - Earliest claimed: 2016-05-19 - Applicants: Robert Bosch GmbH - Inventors: Okke VENEKAMP; Chen ZHOU; Simon Michael HEITZER - Web page: https://patentgrep.com/patent/US20190170047A1 ## CPC - F01N 11/00: Monitoring or diagnostic devices for exhaust-gas treatment apparatus - F01N 3/2066: {Selective catalytic reduction [SCR]} - F16K 7/14: arranged to be deformed against a flat seat - F16K 7/17: the diaphragm being actuated by fluid pressure - F16K 15/1825: {for check valves with flexible valve members} - F16K 31/0655: {Lift valves} - F16K 31/0672: {the valve member being a diaphragm} - F16K 31/1262: {one side of the diaphragm being spring loaded} - F16K 31/1266: {one side of the diaphragm being acted upon by the circulating fluid} - F16K 37/0091: {by measuring fluid parameters} - G01M 3/28: for pipes, cables or tubes; for pipe joints or seals; for valves {; for welds} - F01N 2550/05: Systems for adding substances into exhaust - F01N 2560/08: the means being a pressure sensor - F01N 2610/01: the substance being catalytic material in liquid form - F01N 2610/02: the substance being ammonia or urea - F01N 2610/144: Control thereof - F01N 2900/0412: using pre-calibrated maps, tables or charts - F01N 2900/0416: using the state of a sensor, e.g. of an exhaust gas sensor - Y02T 10/12: Improving ICE efficiencies - Y02T 10/40: Engine management systems - F01N: GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES (arrangements in connection with gas exhaust of propulsion units in vehicles B60K13/00; combustion-air intake silencers specially adapted for, or arranged on, internal-combustion engines F02M35/00; protecting against, or damping, noise in general G10K11/16) - F16K: VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING {(devices for emptying and evacuating the excess liquid in valves or conduits F16L55/07)} - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Disclosed is a stop valve (100) comprising a magnetic yoke (101), a solenoid coil (102), a compression spring (107) and an armature (105) on which an elastic membrane (106) is arranged. The membrane (106) can be sealingly pressed onto at least one fluid connection (108, 109). The stop valve (100) further comprises a guide (111) and a guide pin (110) that is connected to the armature (105). Finally, the compression spring (107) is positioned in such a way as to surround the solenoid coil (102). Also disclosed is a method for detecting leaks and/or identifying variations in metered amounts. Said method, which is carried on in an SCR system comprising the stop valve (100), involves opening the stop valve (100), whereupon a pressurized line is filled with a reducing agent and the stop valve (100) is closed. A pressure is subsequently lowered upstream of the stop valve (100) by shutting off a pump. Finally, any leak is detected and/or variations in the metered amount are identified by having the pressure sensor monitor the pressure downstream ## Claims ### Claim 1 A stop valve (100) comprising a magnet yoke (101), a solenoid coil (102), a compression spring (107), a guide (111, 122, 132), a guide pin (110, 120, 130), and a magnet armature (105), which is connected to the guide pin (110, 120, 130) and on which a flexible diaphragm (106) is arranged, wherein the diaphragm (106) is configured to be sealingly pressed onto at least one fluid connection (108, 109), and the compression spring (107) surrounds the solenoid coil (102). ### Claim 2 (depends on 1) The stop valve as claimed in claim 1, characterized in that the magnet armature is a flat armature or a plunger. ### Claim 3 (depends on 1) The stop valve (100) as claimed in claim 1, characterized in that the guide includes at least one guide bush (111) within the solenoid coil (102), and the guide pin (110) is inserted into said bush. ### Claim 4 (depends on 1) The stop valve (100) as claimed in claim 1, characterized in that the guide includes sliding bearing bushes (122), and the magnet armature (105) rubs along the sliding bearing bushes (122) and is supported by the guide pin (120). ### Claim 5 (depends on 1) The stop valve (100) as claimed in claim 1, characterized in that the guide includes a sliding bearing layer (132), and the magnet armature (105) rubs along the sliding bearing layer (132) and is supported by the guide pin (120). ### Claim 6 (depends on 1) The stop valve (100) as claimed in claim 1, wherein the stop valve (100) is configured to adopt the following modes: a blocking mode, in which the diaphragm (106) closes both a fluid inlet (108) and a fluid outlet (109); a metering mode, in which the stop valve (100) is opened hydraulically in a deenergized condition above a defined pressure; and a reverse suction mode, in which a magnetic force between the magnet yoke (101) and the magnet armature (105) holds the stop valve (100) in an open position. ### Claim 7 (depends on 1) An SCR system (200), comprising a stop valve (100) as claimed in claim 1, a pump (211) and a metering module (230), which are connected together by a pressure line (240), wherein the stop valve (100) is arranged in the pressure line (140), and a pressure sensor (243) is arranged in the pressure line (240) between the stop valve (100) and the metering module (230). ### Claim 8 (depends on 7) A method for detecting leaks and/or identifying variations in metered amounts in an SCR (200) system as claimed in claim 7, wherein the stop valve (100) encloses a pressure (p) in the pressure line (240), the pressure (p) being monitored by the pressure sensor (243), comprising the following steps: opening (300) the stop valve (100); filling (301) the pressure line (240) with reducing agent; closing (303) the stop valve (100); lowering (304) a pressure (p) upstream of the stop valve (100) by shutting off (302) the pump (211); and carrying out (305) leak detection and/or identification of variations in metered amounts by monitoring the pressure (p) downstream of the stop valve (100) by means of the pressure sensor (243). ### Claim 9 (depends on 8) The method as claimed in claim 8, characterized in that the stop valve (100) is closed by the spring force of the compression spring (107). ### Claim 10 (depends on 9) The method as claimed in claim 9, characterized in that a force which presses the diaphragm (106) against a fluid inlet (108) and a fluid outlet (109) is produced by the compression spring (107) when the pressure (p) upstream of the stop valve (100) is lowered (304). ### Claim 11 (depends on 8) The method as claimed in claim 8, characterized in that a first pressure (p1) is built up in the SCR system (200) during the filling (301) of the pressure line (240) with reducing agent, the first pressure (p1) is then reduced to a second pressure (p2), at which the stop valve (100) is closed, and the pressure (p) upstream of the stop valve (100) is then lowered to a third pressure (p3) by switching off (302) the pump (211). ### Claim 12 (depends on 8) The method as claimed in claim 8, characterized in that a drop in the enclosed pressure (p) downstream of the stop valve (100) is detected by the pressure sensor (243) over a defined time period in order to detect leaks. ### Claim 13 (depends on 8) The method as claimed in claim 8, characterized in that, after leakage detection and/or identification of variations in metered amounts, the pressure (p) upstream of the stop valve (100) is increased (306) to a fourth pressure (p4) and the stop valve (100) is opened (307) when the fourth pressure (p4) has been exceeded. ### Claim 14 (depends on 8) A non-transitory computer readable medium comprising program code to perform each step of the method as claimed in claim 8. ### Claim 15 (canceled) ### Claim 16 (depends on 8) An electronic control device (260) which is configured to carry out leak detection and/or identification of variations in metered amounts by means of a method as claimed in claim 8.