Pressure rate of change sensitive latching method and apparatus
AssigneeNorthwest Aerospace Technologies, Inc.
InventorMichael G. Lehmann
Life of this patent
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Abstract
A rate of change in pressure identifies a rapid decompression event in an aircraft, and automatically unlatches a door to allow rapid equalization of pressure throughout the aircraft, allowing for use of doors with greater structural integrity then in current use.
Claims37
A system for monitoring interior pressure change in an aircraft having a bulkhead separating a flight deck portion of the aircraft from a cabin portion of the aircraft, the bulkhead including a door and a latch, the system comprising:
- a first pressure sensor that provides flight deck pressure signals corresponding to a rate of change of an ambient pressure in the flight deck portion of the aircraft and includes:
- a first absolute pressure transducer;
- a first filter stage coupled to filter the output of the absolute pressure transducer;
- and
- a differentiator stage coupled to receive the filtered output of the absolute pressure transducer via the filter and to provide the signals corresponding to the rate of change of the ambient pressure in the flight deck portion of the aircraft;
- and
- a first comparator responsive to the flight deck pressure signals to provide a first actuation signal in response to a comparison of the rate of change of the ambient pressure in the flight deck portion to at least a first minimum reference level.
A system for monitoring interior pressure change in an aircraft having a bulkhead separating a flight deck portion of the aircraft from a cabin portion of the aircraft, the bulkhead including a door and a latch, the system comprising:
- a first pressure sensor that provides flight deck pressure signals corresponding to a rate of change of an ambient pressure in the flight deck portion of the aircraft;
- a first comparator responsive to the flight deck pressure signals to provide a first actuation signal in response to a comparison of the rate of change of the ambient pressure in the flight deck portion to at least a first minimum reference level;
- and
- a solenoid mechanically coupled to operate the latch, the solenoid being responsive to at least the comparison of the rate of change of the ambient pressure in the flight deck portion to the first minimum reference level.
A method of monitoring interior pressure change in an aircraft having a bulkhead separating a flight deck portion of the aircraft from a cabin portion of the aircraft, the bulkhead including a door and a latch, comprising:
- determining a rate of change in an ambient pressure in the flight deck portion of the aircraft, including:
- repeatedly determining the ambient pressure in the flight deck portion of the aircraft;
- filtering the determined ambient pressure in the flight deck portion of the aircraft;
- differentiating the filtered determined ambient pressure in the flight deck portion with respect to time;
- and
- suppressing any rate of change in the ambient pressure in the flight deck portion of the aircraft exceeding a first maximum reference level;
- and
- automatically unlatching the door if the determined rate of change in the ambient pressure in the flight deck portion of the aircraft is between a first minimum threshold and a first maximum threshold, the first maximum threshold greater than the first minimum threshold.
A system for monitoring interior pressure change for an aircraft, the system comprising:
- a first pressure sensor responsive to a rate of change of a first ambient pressure in a first portion of the aircraft to produce an output proportional to the rate of change of the first ambient pressure in the first portion of the aircraft;
- a comparator responsive to the output of the first pressure sensor to control a door locking mechanism based on a comparison of the rate of change of the first ambient pressure to at least a first reference level;
- a latch operable to selectively lock and unlock a door in a bulkhead;
- and
- an actuator coupled to operate the latch to unlock the door in the bulkhead in response to the rate in change of the first ambient pressure in the first portion of the aircraft exceeding a first minimum reference level.
A method of monitoring interior pressure change in an aircraft having a bulkhead separating a flight deck portion of the aircraft from a cabin portion of the aircraft, the bulkhead including a door and a latch, comprising:
- determining a rate of change in an ambient pressure in the flight deck portion of the aircraft;
- and
- automatically unlatching the door if the determined rate of change in the ambient pressure in the flight deck portion of the aircraft is between a first minimum threshold and a first maximum threshold, the first maximum threshold greater than the first minimum threshold.
A method of monitoring interior pressure change in an aircraft having a bulkhead separating a flight deck portion of the aircraft from a cabin portion of the aircraft, the bulkhead including a door and a latch, comprising:
- determining a rate of change in an ambient pressure in the flight deck portion of the aircraft;
- and
- automatically unlatching the door if the rate of change in the ambient pressure in the flight deck portion of the aircraft exceeds a first minimum threshold.
A method of operating a latch of a door in an aircraft, comprising:
- monitoring a rate of change in a first interior pressure of a first portion of an aircraft;
- determining whether the rate of change in the first interior pressure of the first portion of the aircraft satisfies a defined first set of criteria;
- and
- providing an unlatching signal to an actuator to unlatch the door if the rate of change in the first interior pressure in the first portion of the aircraft meets the defined first set of criteria.
A pressure rate sensitive system for use in an aircraft having a flight deck and a cabin separated from the flight deck, the system comprising:
- first rate of change means for determining a rate of change in a pressure in the flight deck;
- first determination means for determining whether the rate of change in the pressure in the flight deck satisfies a defined first set of criteria;
- and
- access controlling means responsive to the first determination means for controlling access between the flight deck and the passenger cabin of the aircraft.
A pressure rate sensitive system for use in an aircraft having a flight deck and a cabin separated from the flight deck, the system comprising:
- first rate of change means for determining a rate of change in a pressure in the flight deck, including:
- a pressure transducer to repeatedly determine a pressure in the flight deck;
- a filter coupled to the pressure transducer to filter noise from an output of the pressure transducer;
- a differentiator coupled to the pressure transducer via the filter to produce a voltage proportional to the rate of pressure change in the flight deck;
- and
- a suppressor coupled to the differentiator to attenuate output from the differentiator above a first maximum reference level and less than a first reference duration;
- first determination means for determining whether the rate of change in the pressure in the flight deck satisfies a defined first set of criteria;
- and
- access controlling means responsive to the first determination means for controlling access between the flight deck and the passenger cabin of the aircraft.
Dependencies are inferred from the claim text.