1. A method for knock detection in a combustion engine, in which combustion is controlled by a control unit, which comprises the steps of,
(a) obtaining at least one sensor signal carrying information of knock intensity within a combustion chamber of the combustion engine;
(b) using different computations for processing the sensor signal to obtain at least two separate sub-values and thereafter combining said sub-values to obtain a knock intensity related detection variable,
(c) comparing said detection variable with a threshold value, and
(d) indicating knock if the value of said detection variable exceeds the threshold value.
2. The method according to claim 1, wherein said processing relates to computations correlated to knock intensity from one and the same sensor.
3. The method according to claim 2, wherein said sensor is an ion-sensor and said sub-values relate to the energy of a characteristic frequency and the integral of the ion current respectively.
4. The method according to claim 2, wherein said sensor is a pressure sensor and said sub-values relate to the energy of a characteristic frequency and the integral of the pressure trace respectively.
5. The method according to claim 1, wherein said processing relates to computation of sensor signals from different sensors.
6. The method according to claim 5, wherein said sensors comprise a combination of at least two of the following:
a. an ion-sensor
b. an accelerometer
c. a pressure sensor.
7. The method according to claim 1, wherein said processing relates to computations of information from different combustion cycles.
8. The method according to claim 7, wherein said information related to knock intensity at cycle k is combined with information from cycle k+1.
9. The method according to claim 8, wherein said information related to knock intensity at cycle k is combined with information from cycle k+2.
10. The method according to claim 1, wherein said control includes comparing said detection variable with a threshold value and said threshold depends on the working point of the engine.
11. The method according to claim 10, wherein said control includes comparing said detection variable with a threshold value and said threshold depends on the sub-values.
12. A system for knock detection in a combustion engine, in which combustion is controlled by a control unit, comprising,
at least one sensor arranged to deliver a sensor signal carrying information of knock intensity within a combustion chamber of the combustion engine,
at least one processing unit arranged to deliver at least two sub-values from the at least one sensor signal and to combine said sub-values to deliver a knock intensity related detection variable,
a comparison unit for comparing the detection variable with a threshold value, and
a control actuation unit for indicating knock if the value of said detection variable exceeds the threshold value.
13. The system according to claim 12, wherein a signal from one sensor is used to deliver said at least two sub-values.
14. The system according to claim 12, wherein at least two signals from at least two sensors are used to deliver at least said two sub-values.
15. The system according to claim 14, wherein said sensors comprise a combination of at least two of the following:
a) an ion-sensor,
b) an accelerometer,
c) a pressure sensor.
16. A method for knock detection in a combustion engine, in which combustion is controlled by a control unit, which comprises the steps of:
(a) obtaining at least one sensor signal carrying information of knock intensity within a combustion chamber of the combustion engine;
(b) using different computations for processing the sensor signal to obtain at least two separate sub-values and thereafter mathematically combining said sub-values in the form
z
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with weighting factors \u03bbl, l=1, . . . L being between 0-1, to obtain a knock intensity related detection variable,
(c) comparing said detection variable with a threshold value, and
(d) indicating knock if the value of said detection variable exceeds the threshold value.
17. A system for knock detection in a combustion engine, in which combustion is controlled by a control unit, comprising,
at least one sensor arranged to deliver a sensor signal carrying information of knock intensity within a combustion chamber of the combustion engine,
at least one processing unit is arranged to deliver at least two sub-values from the at least one sensor signal and to mathematically combine said sub-values in the form
z
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k
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with weighting factors \u03bbl, l=1, . . . L being between 0-1, to deliver a knock intensity related detection variable,
a comparison unit for comparing the detection variable with a threshold value, and
a control actuation unit for indicating knock if the value of said detection variable exceeds the threshold value.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A sprinkler head for emitting water therefrom, the sprinkler head comprising:
an emission portion including openings for emission of water;
a deflector for directing the emission of water; and
a resiliently deformable portion positioned between at least a portion of the emission portion and at least a portion of the deflector to retard entry of foreign matter between the at least a portion of the emission portion and the at least a portion of the deflector.
2. The sprinkler head of claim 1 wherein the deformable portion includes an annular ring.
3. The sprinkler head of claim 2 wherein the annular ring includes an upstanding annular wall for retarding the entry of foreign matter.
4. The sprinkler head of claim 3 wherein the annular ring comprises a base portion for attachment to the emission portion.
5. The sprinkler head of claim 4 wherein the base portion coextends with the annular wall.
6. The sprinkler head of claim 4 further including a securement member for attaching the base portion to the emission portion.
7. The sprinkler head of claim 1 wherein the deformable portion includes a wall positioned on a top surface of the emission portion and extending towards the deflector.
8. The sprinkler head of claim 7 wherein the deformable portion wall may deform inward when force is applied to an outer surface thereof.
9. The sprinkler head of claim 7 wherein the deformable portion wall may deform outward when force is applied to an inner surface thereof.
10. The sprinkler head of claim 9 wherein the deformable portion wall is deformed outward when foreign matter is located between the deformable portion wall and the deflector.
11. The sprinkle head of claim 1 further including a spinning head portion, and the spinning head portion includes the deflector.
12. The sprinkler head of claim 11 wherein the deflector includes vanes located on a surface generally oriented in the downward direction for receiving water from the emission portion for emission from the sprinkler head, the deformable portion includes a wall positioned on a top surface of the emission portion and extending towards the deflector vanes.
13. The sprinkler head of claim 12 wherein the deformable portion wall is deformed outward when foreign matter is located between the deformable portion wall and the deflector vanes.
14. The sprinkler head of claim 13 wherein the deformable portion wall is deformed by force exerted by the deflector forcing the foreign matter from between the deflector and another portion.
15. The sprinkler head of claim 14 further including:
a valve portion for regulating the flow of water through the sprinkler head;
a plug;
a shaft portion on which the spinning head portion and valve portion are rotatably mounted, the spinning head including a recess through which a top portion of the shaft extends, the shaft portion being selectively positionable for adjusting the valve portion by engaging the shaft top portion, the plug being positioned in the recess so as to cover the recess and shaft top portion located therein, and the plug being breachable for receiving a tool for engaging the shaft top portion.
16. A sprinkler head for emitting water outwardly therefrom in an arcuate pattern, the sprinkler head comprising:
a spinning head portion including a deflector;
a braking mechanism for controlling a rate of spin for the head portion;
an emission portion for directing water against the deflector for distribution therefrom; and
a resiliently deformable portion to retard entry of foreign matter into the sprinkler head.
17. The sprinkler head of claim 16 further including a shaft around which the spinning head portion, the braking mechanism, and the deformable portion are positioned.
18. The sprinkler head of claim 17 wherein the spinning head portion shifts upwardly when the deflector is contacted by a water flow from the emission portion.
19. The sprinkler head of claim 18 wherein the braking mechanism is engaged by the upward shifting of the spinning head portion.
20. The sprinkler head of claim 19 wherein the braking mechanism provides a brake force generated by confronting brake pads, and the brake force varies with the flow of water striking the deflector.
21. The sprinkler head of claim 18 wherein the spinning head portion is separated from the deformable portion by a distance when shifted upwardly be water striking the deflector.
22. The sprinkler head of claim 21 wherein at least a portion of the deflector is received by the deformable portion when the water flow through the sprinkler is turned off.
23. The sprinkler head of claim 16 wherein the deformable portion is formed of relatively soft material.
24. The sprinkler head of claim 23 wherein the deformable portion includes a wall extending towards the deflector, and the wall may deform in a direction in which force is applied.
25. The sprinkler head of claim 24 wherein the deformable portion wall is deformed outward when foreign matter is located between the deformable portion wall and the deflector such that the foreign matter is forced out of the sprinkler head.