公开(公告)号：US11828641B2

公开(公告)日：2023-11-28

申请号：US17699526

申请日：2022-03-21

Applicant: Rosemount Inc.

Inventor： Sean Daniel Collins-Dippel

IPC: G01F23/22 ,  G01F25/20 ,  G01F23/296

CPC classification number: G01F23/22 ,  G01F25/20 ,  G01F23/2967

Abstract: A vibrating fork liquid level switch includes a vibrating fork assembly arranged to vibrate at a first frequency when in contact with a process fluid and at a second frequency when in contact with air. A drive circuit connected to the vibrating fork assembly is configured to drive the vibrating fork assembly into oscillation. Sense circuitry senses an oscillation frequency of the vibrating fork assembly. Output circuitry provides a first output when the sensed oscillation is at the first frequency and a second output when the sensed oscillation is at the second frequency. Control circuitry controls power applied to the vibrating fork assembly by the drive circuit between a first and a second power level. Verification circuitry verifies the oscillation frequency of the vibrating fork assembly when power applied to the vibrating fork assembly by the drive circuitry is changed.

公开(公告)号：US20230296421A1

公开(公告)日：2023-09-21

申请号：US17699526

申请日：2022-03-21

Applicant: Rosemount Inc.

Inventor： Sean Daniel Collins-Dippel

IPC: G01F23/22

CPC classification number: G01F23/22

Abstract: A vibrating fork liquid level switch includes a vibrating fork assembly arranged to vibrate at a first frequency when in contact with a process fluid and at a second frequency when in contact with air. A drive circuit connected to the vibrating fork assembly is configured to drive the vibrating fork assembly into oscillation. Sense circuitry senses an oscillation frequency of the vibrating fork assembly. Output circuitry provides a first output when the sensed oscillation is at the first frequency and a second output when the sensed oscillation is at the second frequency. Control circuitry controls power applied to the vibrating fork assembly by the drive circuit between a first and a second power level. Verification circuitry verifies the oscillation frequency of the vibrating fork assembly when power applied to the vibrating fork assembly by the drive circuitry is changed.