Abstract: A method and apparatus for detecting an abnormality in e.g. in operating characteristics or function of a machine, apparatus or system, the method including providing a data sample set comprising n values of a measured physical parameter associated with the apparatus or system generated by repeating a measurement of the physical parameter n times. An extremal measured parameter value is selected from amongst the data sample set, determining a probability of observing the selected parameter value (e.g. of observing a value not exceeding the selected parameter value) by applying the selected parameter value to an extreme value probability distribution function having a location parameter and a scale parameter. The value of the location parameter and the value of the scale parameter are each constructed using an integer value m (e.g. notionally representing the size of a sub-sample data set comprising m of said measured parameter values) in which m is less than n (i.e. m<n).

Abstract: A health monitoring apparatus for a mechanical system includes: a microphone arranged to receive sound from the system; and a processor adapted to process the output of the microphone. The mechanical system may be a gas turbine engine. Further, the engine may have a plurality of bleed valves, each of the bleed valves being configured such that, when open, it produces a sound which is distinguishable from the sounds produced by the other bleed valves, and the microphone being arranged to detect the sound from the bleed valves.

Abstract: A method and apparatus for detecting an abnormality in e.g. in operating characteristics or function of a machine, apparatus or system, the method including providing a data sample set comprising n values of a measured physical parameter associated with the apparatus or system generated by repeating a measurement of the physical parameter n times. An extremal measured parameter value is selected from amongst the data sample set, determining a probability of observing the selected parameter value (e.g. of observing a value not exceeding the selected parameter value) by applying the selected parameter value to an extreme value probability distribution function having a location parameter and a scale parameter. The value of the location parameter and the value of the scale parameter are each constructed using an integer value m (e.g. notionally representing the size of a sub-sample data set comprising m of said measured parameter values) in which m is less than n (i.e. m<n).

Abstract: A method for monitoring the health of a system comprises performing at each of a plurality of times the steps of: constructing a condition signature from a plurality of condition indicators including (a) a plurality of vibration measurements acquired from the system or (b) one or more vibration measurements and one or more performance parameter measurements acquired from the system; predicting a normal signature from a model defining one or more inter-dependencies between said condition indicators, the normal signature corresponding to the condition signature for a healthy system; comparing the condition signature with the normal signature; and registering an event if the condition signature differs from the normal signature by more than a predetermined threshold.

Abstract: A method for monitoring the health of a system comprises performing at each of a plurality of times the steps of:

Abstract: A method and apparatus for diagnosing excessive resistance in an electrical harness of an internal combustion engine. Voltage is applied from a power source (24) through contacts (30a, 30b, 32a, 32b, 34a, 34b, 36a, 36b) and harness leads (26 and 28) to an electrical assembly (20). Electrical assembly (20) includes the load of a first electrical component (23), and by switching means (25) includes the electrical load of a second electrical component (21). An electronic control module (22 or 38) controls switching means (25) and compares the voltage drop across electrical assembly (20) when the second electrical component (21) is switched in or out. By comparing the voltage drops ECM (22 or 38) can determine if there is excessive resistance in the contacts (30a, 30b, 32a, 32b, 34a, 34b, 36a, 36b) or leads (26 and 28).

Abstract: A shaft (12) is connected to a disc (20) by a coupling which comprises a spigot (14) which extends from the shaft (12) and locates in a recess (22) in the disc (20). At ambient temperature there is an interference fit between the spigot (14) and the recess (22) which maintains alignment of the disc (20) and the shaft (12) so that they rotate concentrically. At elevated temperatures the interference fit loosens and alignment of the disc (20) and the shaft (12) is maintained by a plurality of ridges (27) on the face (25) of a flange (24) on the disc (20). The ridges (27) have a large radial component and engage with the confronting face (17) of a flange (16) on the shaft (12) to prevent lateral movement between the shaft (12) and the disc (20).

Abstract: A digital processor implemented electronic governor for engine-generator units including a first control loop for producing a speed error and controlling fuel delivery setting as a function thereof and a second control loop for detecting rack error and producing a field excitation current control signal as a function thereof. Power dips and overruns are voided by modifying rack error as a function of engine acceleration. Means are provided for developing speed errors and rack control signals despite a breakdown in the rack position indicator. Open loop lower power setting controls are provided. Wheel-slip control, power limiting and variable acceleration functions are provided.

Abstract: The pedal effort required to change the setting of a governor (13) of an engine increases sharply with increased engine speed. Booster controls have been provided in the art for applying a boost force (F.sub.B), additive to an operator input force (F.sub.L), for opposing the force (F.sub.S) of a governor spring (42) to thus reduce pedal effort at high engine speeds. The improved booster control (15,15a) herein includes an actuating chamber (53,53a) and a control arrangement (51,51a) for controlling fluid pressure in the chamber (53,53a) when the setting of the governor (13) is changed by the operator and in a predetermined ratio to the operator's input force. The booster control (15,15a) has wider application wherein a boosting force (F.sub.B) is desired to supplement an input force (F.sub.L) for controlling movement of a member (23) having an opposing force (F.sub.S) applied thereto.

Abstract: Governors for diesel engines use a torque-spring to control the slope torque-rise curve as the rack actuator moves between the balance point and full load position. At present, it is difficult to adjust the torque spring mechanism to obtain the correct amount of rack movement between these positions. In the present invention, a first adjustment screw (33) is engageable with the torque spring (20), a second adjustment screw (34) is engageable with a fixed stop member (24), and a means (40) concurrently moves the first screw (33) in spring-deflecting engagement with the torque spring (20) and moves the second screw (34) towards engagement with the stop member (24) in response to fuel-increasing movement of the rack actuator (12), with further fuel-increasing movement of the rack actuator (12) being prevented by engagement of the second screw (34) with the stop member (24).

Abstract: A power plant including an internal combustion engine having a rotary output, a fuel injection pump having a rotary input adapted to be driven by the rotary output in timed relation thereto, and structure interconnecting the input and output including first and second spaced, nonengaging gears, one connected to the input and the other connected to the output, a third gear disposed between and engaging both the first and second gears, a movable carrier journalling the third gear and mounting the third gear for movement whereby the rotational axis of the third gear may be shifted relative to at least one of the first and second gears, and a selectively operable motor connected to the carrier for moving the same to shift the third gear to selectively alter the phasing between the engine and the fuel pump.