US 12,117,092 B2
Electropneumatic solenoid valve, field device having solenoid valve and diagnostic method for electropneumatic solenoid valve
Christof Weigand, Oberursel (DE); and Stefan Kolbenschlag, Darmstadt (DE)
Assigned to Samson Aktiengesellschaft, Frankfurt am Main (DE)
Appl. No. 17/415,591
Filed by SAMSON AKTIENGESELLSCHAFT, Frankfurt (DE)
PCT Filed Dec. 17, 2019, PCT No. PCT/EP2019/085676
§ 371(c)(1), (2) Date Jun. 17, 2021,
PCT Pub. No. WO2020/127282, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 10 2018 132 442.1 (DE), filed on Dec. 17, 2018.
Prior Publication US 2022/0065362 A1, Mar. 3, 2022
Int. Cl. F16K 31/06 (2006.01); F16K 1/44 (2006.01); F16K 37/00 (2006.01); H01F 7/08 (2006.01); H01F 7/16 (2006.01)
CPC F16K 31/0624 (2013.01) [F16K 1/44 (2013.01); F16K 31/0627 (2013.01); F16K 31/0634 (2013.01); F16K 37/0083 (2013.01); H01F 7/081 (2013.01); H01F 7/16 (2013.01)] 18 Claims
 
1. An electropneumatic solenoid valve of a field device of a process plant, comprising:
an electromagnetic actuator having a coil that is configured to be energized and a solenoid armature configured to be movable relative to the coil;
at least one air chamber into which three air channels open, the three air channels comprising a first air channel, a second air channel, and a control air channel;
at least one valve member which, in a first closed position, is configured to close the first air channel and release the second air channel, and which, in a second closed position, is configured to close the second air channel and release the first air channel;
a driver configured to:
be movable in a first actuating direction and in a second actuating direction counter to the first actuating direction, and
connect the valve member to the solenoid armature in a force-transmitting manner;
a driver pretensioning spring, arranged between the driver and the solenoid armature, configured to provide a pretensioning force to the driver in a driving direction corresponding to the first actuating direction or second actuating direction;
a restoring pretensioning spring, arranged between the driver and a core of the electromagnetic actuator that is immovable relative to the coil, configured to provide a restoring force to the driver against the driving direction; and
diagnostic electronics configured to, during an activation of the coil for actuating the solenoid armature, detect a current flowing through the coil, based on a time difference between a first local current flow minimum corresponding to an impact of the valve member on a valve seat and a second local current flow minimum corresponding to an impact of the solenoid armature on a stopper, to provide a diagnostic result.