Multifunction meter for use in an aircraft

• US 4,821,216 A
• Filed: 04/10/1987
• Issued: 04/11/1989
• Est. Priority Date: 04/10/1987
• Status: Expired due to Term

• Current Assignee: Howell Instruments Incorporated
• Original Assignee: Howell Instruments Incorporated
• Inventors: Hartung, Robert L., Howell, John S.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): Teska, Kevin J.
• Application Number:
  US07/036,902
• Time in Patent Office: 732 Days
• Field of Search: 364/550, 364/551, 364/557, 364/424, 364/556, 364/508, 340/971, 340/963, 340/973, 340/52 R, 340/945, 324/990, 324/115
• US Class Current: 701/99
• CPC Class Codes: G01D 7/08 using a common indicating element for two or more variables
• CPC Class Codes: G07C 3/00 Registering or indicating the condition or the working of machines or other apparatus, other than vehicles

Abstract

An indicator monitor which performs a plurality of functions. Both engine exhaust gas temperature and engine rpm are monitored. Based on the engine rpm, it is determined whether the engine is in starting or operating condition. Different parameters and different values are used based on this indication. A plurality of different functions including parameters indicative of temperature in rpm can be monitored by this one meter with a single display and which has electronics that can be housed in an area smaller than the display face.

Claims

1. An indicator assembly for an aircraft that has an engine, said induction assembly comprising:

selecting means for selecting one of a plurality of information values to be displayed, said plurality of information values including information values indicative of;

(a) temperature of said engine, (b) revolution rate of said engine, and (c) temperature of said engine as a function of revolution rate of said engine;

processing means, coupled to signals indicative of a temperature and a revolution rate of said engine, for determining a current value of said one information value based on at least one of said temperature and said revolution rate of said engine, and producing a display signal indicative thereof; and

display means for producing a display output based on said display signal.

2. An indicator assembly as in claim 1 wherein said processing means is also for:

comparing said revolution rate of said engine with a predetermined threshold to determine an operating state of said engine, said operating state being an operating mode when greater than said threshold and an starting mode when less than said threshold,

determining a temperature reference based on said temperature of said engine and said operating state, and

computing a temperature relation as a function of said temperature of said engine and said temperature reference and wherein said selecting means can also select said temperature relation to be displayed.

3. An assembly as in claim 1 wherein said processing means is also for:

comparing said revolution rate of said engine with a predetermined threshold;

determining which of at least two different temperature limits should be used on said revolution rate; and

producing a different display signal for each limit, said display signal being displayed on said display means.

4. Assembly as in claim 1 further comprising:

memory means for storing maximum and minimum revolution rates within a predetermined time period; and

means for determining a low cycle fatigue value using said maximum and minimum revolution rates.

5. An indicator assembly as in claim 1 wherein said processing means also determines whether said engine of said aircraft is in operate mode or in start-up mode based on said revolution rate of said engine, and wherein said information value (c) is a temperature overlimit value, based on a temperature comparison with a variable limit that varies based on said determination.

6. Assembly as in claim 1 wherein a plurality of different ones of said information values can be sequentially displayed, and wherein said selecting mean sequentially cycles between different ones of said plurality of information values.

7. Assembly as in claim 4 wherein one of said information values is normally being displayed, and said selecting means selects one of said plurality of information values other than said one which is usually being displayed.

8. Assembly as in claim 7 wherein temperature is said value usually being displayed.

9. Apparatus as in claim 7 wherein said information values other than said one which is usually displayed, is displayed for a limited time, after which said one information value which is usually displayed, is again displayed.

10. Assembly as in claim 7 further comprising a ball relay, coupled to said processing means, for indicating a warning condition.

11. Assembly as in claim 7 wherein said display means includes a warning indication area thereon said warning indication driven by said processing means.

12. Assembly as in claim 7 wherein said display means is a single display unit.

13. Assembly as in claim 7 further comprising a chassis in which said processing means and said selecting means are mounted, said chassis being of a cross sectional area smaller than an area size of said display means.

14. Assembly as in claim 7 wherein said processing means is also for causing a flashing display between a title indicative of an information value, and a number indicative of a value of said information value, when an information value other said usually displayed information value is selected.

15. Assembly as in claim 14 further comprising a plurality of buffers for receiving input signals to be connected to said processing means.

16. Assembly as in claim 15 further comprising:

means for obtaining a measurement of a temperature of said engine and producing a temperature output indicative thereof; and

means for obtaining a measurement of a revolution rate of said engine and producing a revolution output indicative thereof.

17. An indicator assembly for an aircraft with an engine, said indicator assembly comprising:

processing means for;

(a) receiving signals indicative of a temperature of said engine and a revolution rate of said engine,

(b) comparing said revolution rate with a predetermined threshold of revolution rate to determine an operating state of said engine, said operating state being an operating mode when greater than said threshold, and a starting mode when less than said threshold,

(c) determining a temperature reference based on said operating state, and

(d) computing a temperature relation as a function of said temperature reference and said temperature of said engine; and

means for displaying said temperature relation.

18. An assembly as in claim 17, further comprising mode selecting means for selecting one of a plurality of information values, to be displayed.

19. Apparatus as in claim 18 wherein one information value is usually displayed, and other information values, including said temperature relation, are selected by an operation of said mode selecting means.

20. Apparatus as in claim 19 said usually displayed information value is temperature of said engine.

21. Apparatus as in claim 19 wherein there are a plurality of information values, and said mode setting means switches between said plurality of information values by choosing a next information value in a serial order.

22. Apparatus as in claim 19 further comprising a chassis housing said processing means, therein said chassis has a smaller cross-sectional area than an area of said displaying means.

23. An indicator assembly for an aircraft engine, comprising:

a display information value to be

means for selecting a particular information displayed from a plurality of information values, said plurality of information values including values indicative of;

(a) temperature, (b) revolution rate and (c) functions of temperature as compared with a reference that is based on revolution rate;

processing means for;

(a) receiving signals indicative of temperature and revolution rate of said engine,

(b) normally displaying a temperature of said engine on said displaying means,

(c) detecting a selection by said select

(d) obtaining a value indicative of said particular information value, only for a predetermined time after said c) detecting a selecting function, and

(e) displaying said value only during said predetermined time while it is being obtained, said displaying being on a same display area that said temperature is normally displayed on; and

a chassis for mounting said selecting means and said processing means, said chassis having a cross-sectional area smaller than an area of said display.

24. Apparatus as in claim 23 wherein said processing means is also for f) flashing between a label indicative of said information to be displayed, and a value of said information to be displayed.

25. Apparatus as in claim 23 wherein said display is a single display.

26. An indication assembly for an aircraft engine, comprising:

display;

means for selecting a particular information value to be displayed on said display from a plurality of information values, said plurality of information values including;

(a) a condition during starting mode where temperature is greater than a first threshold , (b) a condition during operation mode where temperature is greater than a second threshold, (c) revolution rate greater than a danger revolution rate times a proportionality constant, (d) peak temperature value during start mode, (e) time above certain temperature during start operation, (f) peak temperature during operating mode, (g) time above certain temperature during operating mode, (h) engine speed peak, (i) time above a red line value of revolution rate times a proportionality constant, (j) engine operating hours in operating mode, and (k) engine cycles;

processing means for;

(a) receiving signals indicative of temperature and revolution rate of said engine;

(b) normally displaying a temperature of said engine;

(c) detecting a selection by said selecting means;

(d) incrementing a pointer each time a selecting by said selecting means is detected, said pointer indicative of which of said plurality of information values is selected;

(e) obtaining a value indicated by a value of said pointer, said obtaining occurring only for a predetermined time period after said detecting a selecting function;

(f) displaying on said display said information value indicated by said pointer, alternately with a label indicative of said information value, flashing between said label and said value occurring at predetermined intervals, said displaying occurring only during said predetermined time period after said detecting a selection function; and

(g) returning to said display of a temperature of said engine and resetting said pointer after said predetermined time period elapses, unless another selection is detected; and

a chassis attached to said display and housing said selecting means and said processing means, said chassis having a cross sectional area of a size smaller than an area of said display.

27. A method for indicating a plurality of information values on a display, in an aircraft that has a engine, comprising the steps of:

selecting one of a plurality of information values to be displayed, said plurality of information values including information values indicative of;

(a) temperature of said engine, (b) revolution rate of said engine, and (c) temperature

receiving signals indicative of a temperature and a revolution rate of said engine;

determining a current value of said one information value based on at least one of temperature and revolution rate of said engine;

producing a display signal indicative thereof; and

displaying a display output based on said display signal.

28. A method as in claim 27 comprising the further steps of:

comparing said revolution rate of said engine with a predetermined threshold, to determine an operating state of said engine as being in an operating mode when greater than said threshold and in a starting mode when less than said threshold,

determining a temperature reference based on said operating state, and

computing a temperature relation as a function of said temperature of said engine and said temperature reference.

29. A method as in claim 27 comprising the further steps of:

storing maximum and minimum revolution rates within a predetermined time period; and

determining a low cycle fatigue value based on said maximum and minimum values.

30. A method as in claim 27 comprising the further step of determining whether said engine of said aircraft is in operate mode or in start-up mode based on said revolution rate of said engine, and computing said information value (c) as a temperature overlimit value, based on a temperature comparison with a variable limit that varies based on said determination.

31. A method as in claim 30 comprising the further steps of:

comparing said revolution rate of said engine with a predetermined threshold;

determining which of at least two different temperature limits should be used, based on a result of said comparing; and

producing a different display signal for each limit, said output being displayed on a display means.

32. A method as in claim 30 comprising the further steps of sequentially displaying different ones of said information values, and sequentially cycling between different ones of said plurality of information values for each selecting.

33. A method as in claim 32 comprising the further step of causing a flashing display between a title indicative of an information value, and a number indicative of a value of said information value, when an information value other said usually displayed information value is selected.

34. A method as in claim 32 further comprising the step of calibrating said meter.

35. A method as in claim 32 wherein one of said information values is normally being displayed, comprising the further steps of selecting one of said plurality of information values other than said one which is usually being displayed.

36. A method as in claim 35 wherein temperature of the engine is the value usually being displayed.

37. A method as in claim 36 wherein said information values other than said one which is usually displayed, are only displayed for a limited time, after which said one information value which is usually displayed, is again displayed.

38. A method for indicating information values on a display associated with an engine, comprising the steps of:

receiving signals indicative of a temperature of said engine and a revolution rate of said engine;

comparing said revolution rate with a predetermined threshold of revolution rate to determine an operating state of said engine as being in an operating mode when greater than said threshold, and in a starting mode when less than said threshold;

determining a temperature referenced based on said operating state;

computing a temperature relation as function of said temperature reference and said temperature of said engine; and

displaying said temperature relation.

39. A method as in claim 38 comprising the further steps of selecting an information value from a plurality of information values, to be displayed.

40. A method as in claim 39 wherein one information value is usually displayed, and other information values are selected in said selecting step.

41. A method as in claim 40 wherein said usually displayed information value is temperature of the engine.

42. An method of indicating information on a display associated with an aircraft engine, comprising the steps of:

selecting a particular information value to be displayed from a plurality of information values, said plurality of information values including values indicative of;

(a) temperature, (b) revolution rate and (c) functions of temperature as compared with a reference that is based on revolution rate;

receiving signals indicative of temperature and revolution rate of said engine;

normally displaying a temperature of said engine;

detecting a selecting in said selecting step;

obtaining a value indicative of said particular information value, only for a predetermined time after said detecting a selection step; and

43. A method as in claim 42 comprising the further step of determining whether said engine of said aircraft is in operate mode or in start-up mode based on said revolution rate of said engine, and computing said information value (c) as a temperature overlimit value, based on a temperature comparison with a variable limit based that varies on said determination.