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US 3,940,622 AGranted
Icing detector
AssigneeCanadian Patents and Development Limited
InventorsJames R. Stallabrass, T. Rayman Ringer, Donald L. Bailey, Patrick F. Hearty
Life of this patent
Estimating the term…
Abstract
An icing detector for moving or stationary installations which comprises a probe subject to atmospheric icing, and ice formation sensing means disposed in a duct through which flow of ambient air is induced by ejector defining elements. The induced air flow provides high sensitivity regardless of the relative ambient velocity. An ice/de-ice cycle is repeated providing continuing icing detection. Specific embodiments of the invention provide a measure of icing severity or ambient liquid water content.
Claims20
An icing detector, for detecting the presence in the atmosphere of supercooled droplets, comprising:
- a. a duct member having an annular plenum formed in one end thereof;
- b. means for supplying pressurized gas to said plenum;
- c. primary jet outlet means communicating with said plenum, said primary jet outlet means being disposed within the duct to induce secondary ambient air flow through the duct;
- d. a probe mounted within said duct member so that supercooled water droplets suspended in the induced secondary ambient air flow impinge on said probe and form ice thereon;
- and
- e. sensing means for detecting the presence of ice on said probe comprising an emitter for emitting radiation that is attenuated by ice and a radiation sensor, said emitter and sensor being mounted in the duct member so that ice formed on the probe occludes the radiation from the emitter to the sensor.
3 more elements
An icing detector, for detecting the presence in the atmosphere of supercooled droplets, comprising;
- a. A duct member having a plenum formed in one end thereof;
- b. means for supplying pressurized gas to said plenum;
- c. primary jet outlet means communicating with said plenum, said primary jet outlet means being disposed within the duct member to induce secondary ambient air flow through the duct;
- d. a probe mounted within said duct member so that supercooled water droplets suspended in the induced secondary ambient air flow impinge on said probe and form ice thereon;
- e. probe heating means for periodic melting of ice formed on the probe;
- f. a radiation emitter for emitting radiation that is attenuated by ice and a radiation sensor mounted within said duct member, said emitter and sensor cooperating with the probe to detect ice formation on the probe by the occlusion of radiation from the emitter to the sensor;
- g. means for producing a signal related to the magnitude of radiation received by said sensor;
- h. means responsive to a predetermined lower signal level for initiating probe heating and means responsive to an upper signal level for terminating probe heating;
- i. means for determining the rate of signal change between the upper and lower levels;
- and
- j. indicator means responsive to the rate of signal change to provide a quantitative indication of the ambient icing condition.
8 more elements
An icing detector, for detecting the presence in the atmosphere of supercooled droplets, comprising:
- a. a duct member having a plenum formed in one end thereof;
- b. means for supplying pressurized gas to said plenum;
- c. primary jet outlet means communicating with said plenum, said primary jet outlet means being disposed within the duct member to induce secondary ambient air flow through the duct;
- d. a probe mounted within said duct member so that supercooled water droplets suspended in the induced secondary ambient air flow impinge on said probe and form ice thereon;
- e. probe heating means for periodic melting of ice formed on the probe;
- f. a radiation emitter for emitting radiation that is attenuated by ice and a radiation sensor mounted within said duct member, said emitter and sensor cooperating with the probe to detect ice formation on the probe by the occlusion of radiation from the emitter to the detector;
- g. means for producing a signal related to the magnitude of radiation received by said sensor;
- h. means responsive to a predetermined lower signal level for initiating probe heating and means responsive to an upper signal level for terminating probe heating;
- i. means for producing a time interval signal related to the time interval in progressing from the upper signal level to the lower signal level;
- and
- j. means responsive to the magnitude of said time interval signal to provide a quantitative indication of the ambient icing condition.
8 more elements
An icing detector, for detecting the presence in the atmosphere of supercooled droplets, comprising:
- a. a duct member having a plenum formed in one end thereof;
- b. means for supplying pressurized gas to said plenum;
- c. primary jet outlet means communicating with said plenum, said primary jet outlet means being disposed within the duct member to induce secondary ambient air flow through the duct;
- d. a probe mounted within said duct member so that supercooled water droplets suspended in the induced secondary ambient air flow impinge on said probe and form ice thereon;
- e. probe heating means for periodic melting of ice formed on the probe;
- f. a radiation emitter for emitting radiation that is attenuated by ice and a radiation sensor cooperating with the probe to detect ice formation on the probe by the occlusion of radiation from the emitter to the sensor;
- g. means for producing a signal related to the magnitude of radiation received by said sensor;
- h. means responsive to said signal crossing a predetermined signal level corresponding to occlusion of a major portion of the radiation for initiating probe heating;
- i. timing means for terminating probe heating after a predetermined time interval provided that the signal has recrossed said predetermined signal level, but allowing repetition of probe heating for another of said time intervals if the signal has not recrossed said predetermined signal level;
- and
- j. indicator means for indicating activation of the probe heating means.
8 more elements
Dependencies are inferred from the claim text.