公开(公告)号：US20200240422A1

公开(公告)日：2020-07-30

申请号：US16742074

申请日：2020-01-14

Applicant: ROLLS-ROYCE plc

Inventor： Ralph W. HILL

IPC: F04D27/00 ,  F02C7/36 ,  G01D5/02

Abstract: A monitoring system for monitoring behaviour of a rotating shaft is provided. The system includes a phonic wheel which is mounted coaxially to the shaft for rotation therewith, the phonic wheel having a number N of teeth in a circumferential row. The system further includes a first sensor configured to detect the passage of the teeth of the phonic wheel by generating a first alternating measurement signal which includes (i) a primary oscillatory component having a frequency of fN, where f is the rotational frequency of the shaft, and (ii) a secondary oscillatory component of frequency f when the phonic wheel precesses such that each revolution of the shaft a clearance between the phonic wheel and the first sensor cyclically varies between a maximum value and a minimum value. The system further includes a processor unit configured to determine the durations of successive first speed samples, each first speed sample being a block of integer n successive cycles of the primary oscillatory component of the first alternating measurement signal. The secondary oscillatory component of the first alternating measurement signal, when present, produces a cyclical variation of frequency fin the durations of the successive first speed samples. The processor unit is further configured to detect any such cyclical variation of the first speed samples and to compare a detected cyclical variation of the first speed samples against a threshold variation to determine therefrom if the phonic wheel is precessing.

公开(公告)号：US20190285004A1

公开(公告)日：2019-09-19

申请号：US16265022

申请日：2019-02-01

Applicant: ROLLS-ROYCE plc

Inventor： Ralph W. HILL

IPC: F02C9/46 ,  F16K17/36 ,  F16K39/02 ,  F02C7/228 ,  F02C7/232

Abstract: A fault-accommodating flow scheduling valve has a first inlet, outlet, and orifice therebetween. The valve has a shuttle valve member on the orifice inlet side, a primary valve member on the orifice outlet side, a compression-loaded primary spring, and first and second compression-loaded balance springs. Below a threshold differential pressure, the primary valve member engages with the outlet-side sealing face to close the valve while the shuttle valve member is spaced from the inlet-side sealing face, and on failure of the primary spring, the primary valve member moves from the outlet-side sealing face but the shuttle valve member closes the valve. Above the threshold differential pressure, the primary valve member opens the valve while the shuttle valve member remains spaced, and on failure of the primary spring, the primary valve member moves further from the outlet-side sealing face but the shuttle valve member closes the valve.