JPS5899809A - Air pressure control method and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for controlling the air pressure in a closed space such as an airplane cabin, and in particular to monitoring and testing each component to improve the reliability of its operation and ensure the safety and comfort of passengers in the closed space. The present invention relates to a digital in-flight pressure control method and device that can increase the internal pressure.

Air pressure regulation in the passenger cabin (hereinafter also referred to as the cabin) is an important element in providing a comfortable environment for passengers and crew members and in ensuring safe flight of the airplane. Most of today's airplanes fly at altitudes of 35,000 feet (approximately 11,067 degrees Celsius) or higher, and cabin pressure control systems used in such airplanes must satisfy the following conditions.

In other words, sufficient oxygen is supplied to passengers without causing unpleasant sudden changes in cabin pressure that are felt to the human ear, and without increasing the difference between cabin pressure and outside pressure excessively, and ensuring that the components of the airplane are properly fed. Do not apply excessive force.

With conventional cabin pressure control systems, it is convenient for one crew member to periodically measure the cabin altitude (pressure) (in-cabin pressure, i.e., the cabin pressure line) to compare it with the flight altitude, so it is convenient to express it in terms of the altitude that produces the cabin pressure. Compare the rate of change in the readings of the measuring instrument (hereinafter referred to as cabin altitude) with the rate of change in the readings of the airplane's altimeter to determine whether the device is operating normally. In addition, in many conventional systems, the cabin pressure is determined based on the takeoff runway altitude, cruising altitude, and landing altitude based on sea level, but there are cases where the cabin pressure changes suddenly. A) Because of this, there were fishing gear that caused passengers and crew members to feel uncomfortable as their ears were exposed to changes in air pressure.

Traditional equipment has been unreliable because it lacks the self-monitoring and testing capabilities and flight data required for modern airplanes.

This minimizes crew effort, maintains constant cabin pressure regardless of changes in the aircraft's altitude and environment, and provides high safety and reliability for monitoring and testing critical components. It was strongly desired to provide a pressure control device (in-flight).

According to the present invention, there is provided a safe and reliable cabin pressure control method and device that eliminates the above-mentioned drawbacks of conventional devices, is applicable to the latest model airplanes, and provides a comfortable environment for passengers and crew members. is provided. The only operations that require manual input to the device are selecting the landing runway altitude and the maximum rate of change of cabin pressure before takeoff. Also, there is no need to change during the flight unless the landing site is changed. The device of the present invention can minimize changes in cabin pressure independently of changes in airplane altitude and external pressure. The logic circuitry of the device can also automatically perform adjustment actions according to the airplane's flight plan to eliminate passenger and crew discomfort due to low pressure at high altitudes.

Apparatus according to the invention has a maximum range of ±500 feet (approximately ±15 feet).
A cruise altitude control system is included to maintain the cabin altitude (pressure) at a constant value when flying within a range of altitude changes of 2m. When the cruise altitude control system detects that the altitude change of the airplane is within a predetermined limit range, the cabin pressure control system fixes the cabin altitude according to the schedule and maintains the cabin altitude at the predetermined cabin altitude. Function. Therefore, until the airplane rises or descends to a predetermined height from the cruise control altitude, or until the difference between the cabin pressure and the outside pressure reaches a predetermined limit value, The cabin altitude (pressure) can be kept constant independently of the accompanying altitude changes of the airplane. When the cruising altitude of the airplane changes beyond a predetermined range, the cruising altitude control device is released from the fixed state and the cabin altitude (
pressure) is increased or decreased at a predetermined rate to the timetable value corresponding to the new altitude.

Hereinafter, the present invention will be explained along with preferred embodiments.

- The cabin pressure control system according to the present invention shown in FIG. 1 includes a mode selector 12 for selecting an operating mode, and the mode selector 12 indicates the operating state of the airplane before takeoff, during takeoff, and during landing. A signal is given to the OR gate 14 indicating an inspection on the ground after landing. When the OR gate 14 receives a signal from the mode selector 12, it outputs a signal to the OR gate 16. In addition, when in the automatic operation mode, the automatic flight control circuit 18 also outputs the O
A signal is sent to the R gate 16 to control cabin pressure based on external pressure, landing altitude, and actual cabin pressure. On the other hand, an in-flight pressure sensor 20 detects the pressure inside the aircraft, and a signal Pc indicating the actual pressure inside the aircraft is inputted to the automatic flight control circuit 1B via an A/D converter 22. In addition to the signal from the automatic flight control circuit 18, the logic circuit 19 also inputs a signal indicating the maximum permissible pressure difference between the external pressure and the actual pressure inside the aircraft, and sends the output signal to the OR gate 16 and the limit circuit. Output to 26. The limiting circuit 26 also receives the output signal from the OR gate 16.

The output signal of the logic circuit 19 indicates the actual pressure difference between the internal pressure and the external pressure, or the maximum allowable differential pressure between the internal pressure and the external pressure. In logic circuit 26, a predetermined rate of change in cabin pressure is calculated for the operating mode of the airplane selected by operating mode selector 12.

The D/A converter 28 inputs the digital output signal from the logic circuit 26 and outputs an analog signal P0° representing the predetermined rate of change of the internal pressure to the adding circuit 30. Analog differentiator 32 receiving output P0 of in-machine pressure sensor 20
differentiates the actual internal pressure signal and sends a signal indicating the actual rate of change of the internal pressure to the amplifier 34, and the amplifier 34 outputs a signal POA indicating the actual rate of change to the adding circuit 30. On the other hand, the adder circuit 30 sends a signal representing the difference between the predetermined rate of change and the actual rate of change in the internal pressure to the amplifier 36, and the amplifier 36 itself inputs a signal representing the difference in the rate of change to the adder circuit 38. Output a signal.

On the other hand, the addition circuit 38 also receives a signal representing the speed of the drive motor 42 from the tachometer 40 via the speed demodulation circuit 44 . The output signal of the adder circuit 38 is amplified in an error amplifier 46 to provide an error signal that drives the drive motor 42. More specifically, one of the valve open switch 48 and the valve close switch 50 is activated to operate the drive motor 42 in accordance with the error signal. The drive motor 42 controls the intake valve 52, determines the flow rate of air from inside the machine, and adjusts the pressure inside the machine.

If a failure occurs in the circuit described above, the drive motor 42 will be controlled via the standby control circuit 53 having the same configuration as the circuit described above.

The block diagram of FIG. 2 shows the flow of input and output signals from a central processing unit 54 (hereinafter simply referred to as CPU) for controlling valve 52 (not shown in FIG. 2). A voltage of ±15 V is applied to the in-machine pressure sensor 20 from a power source 60, and a signal P is generated which detects the in-machine pressure and indicates the detected value. to channel 0H-0 of analog multiplexer 56. On the other hand, the analog multiplexer 56 inputs a plurality of analog signals, selectively converts them into digital signals, and sends the signals to the CPU 54. The first input terminal of the adder 58 receives the output signal P0 from the in-machine pressure sensor 20, and the second input terminal receives the offset voltage "OFν" from the power supply 60.
A route-type signal PLrM indicating the landing runway altitude is inputted from the voltage divider 62 via the filter 64 to the input terminals of the respective input terminals. The voltage divider 62 receives an input voltage VR from a reference voltage source 65.
11iF and outputs a signal PLXN.

The adder 58 outputs the signal P-IJ and the in-machine pressure P. A signal P representing the difference between the two is outputted and sent to an amplifier 66. amplifier 6
6 inputs the signal pvxyr, amplifies it, and sends it to the analog multiplexer 560 input channel 0H-1. The input terminal 67 of the in-machine pressure sensor 20 receives an input signal P of an in-machine pressure control device that simulates the in-machine pressure during the bench test. B Engineering M has been sent. Signal PXrXM from filter 64 is also sent to analog multiplexer 260 input channel 0H-2.

Channel 0H-3 of analog multiplexer 56 also receives a signal representing a predetermined maximum rate of change in cabin pressure. That is, the voltage divider 68 receives the voltage vR from the reference voltage source 65.
is divided into voltages and passed through a filter 70 to an analog multiplexer 5.
6 channel CH-3.

Channel 0R-4 of analog multiplexer 56 is for checking the ±15T output voltage of power supply 60;
Input the signal from the bench test switch 72 to 0PU54
command to set the operation to bench test mode. power supply 60
The output voltage of +15V is connected to channel OH- through resistor 74.
4, the output voltage -157 of power supply 60 is also applied to channel 0H-4 via resistor 76.

Channel 0R-5 of analog multiplexer 56 has
A signal representing the speed of a drive shaft 40 (not shown in FIG. 2) is input. On the other hand, the adder 78 inputs the output signal from the speed demodulation circuit 44 (not shown in FIG. 2) via the amplifier 79 and the reference voltage from the reference voltage source 65 via the amplifier 82. 83 to channel 0H-5 of the analog multiplexer 56.

In addition, a signal representing a predetermined rate of change in the cabin pressure POO is input to channel CH-6 of the analog multiplexer 56.
The actual rate of change POAB in the cabin pressure is input to channel 0H-7.

On the other hand, channels CH-8 and CH-9 of analog multiplexer 56 are provided with valves 52 (not shown in FIG. 2) opened by drive motor 40 (not shown in FIG. 2). The valve 5 is driven by a signal representing the drive motor 40.
A signal indicating that 2 is closed is inputted respectively. The reference voltage "R1ν" from the reference voltage source 65 is input to channel 0H-10, and the internal reference ground signal is input to channel 0H-11. Channels 0H-12, 0H
-14, 0H-15#'i This is a spare terminal. In addition, channel 0R-13 receives an output signal from voltage drop monitoring circuit 84 that monitors the 5V output voltage from power supply 60.

To read the analog signal input to a particular channel of analog multiplexer 56, CPU 54 first addresses that particular channel via latch circuit 86. Accordingly, the analog multiplexer 56 outputs the output voltage to the adder circuit 90 via the buffer amplifier 92. The data from the DATA terminal of 0PI754 is DATA
It is sent to latch circuit 86 via bus 85 and data buffer amplifier 88. The four output terminals of the latch circuit 86 are connected to the address terminals of the analog multiplexer 56, and the input channel 0H of the analog multiplexer 56 is connected to the address terminal of the analog multiplexer 56.
-0 to 0H-16 are selectively addressed.

CPU 54 also outputs a digital signal representing a predetermined voltage to D/A converter 28 via latch circuit 86.

The D/A converter 28 converts the digital input signal into a corresponding analog voltage based on the voltage %RIA input from the reference voltage source 65 via the amplifier 94. Inverter 96 inverts the analog output voltage from D/A converter 28 and sends the inverted voltage vDlk to addition circuit 90, comparison circuit 97, and sample holding circuit 98.

The adder circuit 90 also has an offset voltage V. Fν8ffiTl
input voltage of the addressed channel of analog multiplexer 56 and D/A converter 2.
A voltage representing the difference from the output voltage of 8 is output. One comparator circuit 100 inputs the output voltage from the adder circuit 90,
A digital signal indicating whether the output voltage of adder circuit 90 is positive or negative with respect to input terminal 7 of input buffer 1010 is output.

According to another embodiment of the invention, another input buffer 10
2, 103 may be attached. In this case, input buffer 1
02 and 103 supply digital signals representing the state of predetermined flight variable data to the 0PU 54 in order to zero-check the predetermined conditions of the cabin pressure control system. For example, inverter 96
To check whether the output of is over 5V,
The output terminal DAO1 of the comparison circuit 97 is connected to the input buffer 102.
0 input terminal O.

In the illustrated embodiment, each input buffer 101, 102
103 contains eight data bits 0-7 and a digital escape signal that enables each data bit to be selectively input to CPU 54. Under the control of the 0PU 54, each input buffer 101-103 is addressed using digital successive signals from each output terminal 4, 3.2 of the address decoder 104 shown in FIG.

In order to read out the addressed channel of the analog multiplexer 56, the 0PU 54 transfers the address decoder 104 output terminal 4 to the input buffer 101 (second B
), and the buffer 101 operates to output the digital successive signal 1 to the input terminal of the
It operates to input signals from oo to the CPU 54 manually.

The 0PU 54 determines the output voltage of the analog multiplexer 56 by a continuous approximation method. The output of the comparison circuit 100 is higher than the output voltage of the analog multiplexer 56 by a voltage v'Q.
If /A is higher, the CPU 54 outputs a digital signal representing the second predetermined voltage to the D/A converter 28 via the latch circuit 86.

The above operations are repeated until 0PU 54 generates a signal that approximates the output of analog multiplexer 56 within specified tolerances. C with the above-mentioned 9m selling method! PU 54 will read each channel of analog multiplexer 56. Furthermore, other information supplied to the 0PU 54 via the buffers 101, 102, and 103 will be explained below.

The present invention is configured to input information regarding flight variables to the cabin pressure control system based on one or more computers on board the aircraft. In the illustrated embodiment, the multiplexer 108 is connected to the first and second computers 110.
, 112. CPU 54 is computer 11
0 or 112 is determined, and a computer selection signal is sent from the CPU 54 to the selection input terminal of the multiplexer 108 via the output terminal 7 of the output port 7a 113 shown in FIG. .

Referring to FIGS. 2A, 2B, 2C, and 3, a data input circuit 116 for inputting onboard data is connected to an output terminal of multiplexer 108 and is connected to a selected computer 110 or , 112 are input and conditioned. Typically, each information word is 32-bit data transmitted in a zero return format. The first 8 bits constitute the identification code of the transmitted information word, the other bits represent flight data. The data input circuit 116 is 3
Store all 2-bit data and then OR the interrupt signal.
CP through gate 117 and flip-flop 11g
It is sent to the interrupt request input terminal of U54.

Referring to FIG. 3, the address decoder 120 is
The address decoder 121 is connected to the address decoder 120, and the address decoder 104 is connected to the address decoder 121, respectively, so that jl)C! PU 54 may selectively address other components of the cabin pressure control system.

A read/shift input terminal and a reset input terminal of data input circuit 116 are connected to output terminal 5 of address decoder 104 and output terminal 3 of address decoder 120, respectively. 117 also inputs a periodically generated output signal from time frame generator 126 which provides interrupt operation of 0PU 54.

crty541d, outputs the resume frame signal to the time frame generator 1 via the output terminal 2 of the address decoder 120.
26, the time frame generator 12
6 starts. Time frame generator 126
The output signal FMG of is sent to the input buffer 1030 input terminal 7 and the slip 70 knob 128. When an electrical failure occurs in the cabin pressure control device, a disconnection signal is sent from the 0PU 54 to the tree flop 128 and the second 7-lip flop 130 via the output buffer 113. In response to this, an automatic failure signal is output from the flip-flop 128 to the input terminal l of the input box 7a 101, and the CPU S4
It becomes possible to monitor the operation of the Kyo shift flip 70 tube 12g.

If there is no fault in the cabin pressure control system (0PU54 is input when a signal indicating removal of a previously existing fault is input to CPU54)
A fault removal signal is sent to the 7-lip 70 block 128 via the output terminal 7 of the address decoder 104, and the 7-lip flop 128 outputs a signal to another 7-lip 70 block 130. The 7-rip 7-4 130 also receives a relay activation signal from the 0PU 54 via the output terminal 7 of the address decoder 120. In response to these signals, the 7-lip 70 tube 130 outputs a signal that activates the relay drive logic circuit 134. When relay drive logic 134 is activated, relay drive logic 134 outputs input
Sends a relay-on signal to input terminal 1 of 3. To properly operate the cabin pressure control system, K must sequentially turn on the time frame generator 126, flip-flop 128, and flip-flop 130 to activate the relay drive logic circuit 134; If a failure occurs, the above-described operations are interrupted, and control of the cabin pressure by the cabin pressure control device is stopped.

A signal output from the reset circuit 136 to reset or turn on the cabin pressure control device 10 is transmitted to the clip 70 knob 118.
, one-shot multivibrator 138 and AND game) 14G, said AHD goo) 1
40 has one-shot multi-function ibrator 138
The output signal from is input. When the set time in the one-shot multivibrator 138 is reached, the AN
Reset terminal R chicken 81 from D gate 140 to 0PU54
A reset signal is sent to the CT.

C! When the PU 54 is reset, the initial values of the control parameters are set and the cabin pressure control system is placed in the ground operating mode. The reset circuit 136 is energized (by the voltage TRIv from the reference voltage source 65 and the 5v voltage from the power supply 60).

The 0PU 54 has two operating levels: 7 or ground and background. The foreground level is used to store data and functions that must be processed according to timing constraints, such as reading information from the data input circuit 116, updating cabin pressure measurement input, and outputting. This includes updating the rate of pressure change and running certain high priority tests. On the other hand, the background level is used to provide functions that do not need to be updated according to timing constraints.
Contains parameters, etc. 0PU54 is normal time.
It operates within a time frame set by frame generator 1261C.

If time frame generator 126 generates an interrupt signal every 50 milliseconds, CPU 54 responds to the interrupt signal by going into foreground processing mode. When the calculation regarding 7 or ground is completed, the CPU 54 calculates the remaining time in the 7 frame and background until a new timing frame interrupt signal is input to the input terminal IRQ of the interrupt request. returned to mode.

Unless an activation signal is input from the data input circuit 116 to the data input circuit 117, the 0PU 54 performs normal operation within a predetermined time frame, in which case the 0PU 54 is returned to the foreground processing mode and the data input circuit 11
6 IC stored data words need to be processed. 0
From PU54, 8. A read/shift signal is input to the read/shift input terminal of the data input circuit 116 via the output terminal 5 of the address decoder 104, and the data input circuit 11
The data word stored in 6 is data mother #! 0 through 85
It is input to PU54.

Although the information inputted by the data input circuit 116 is diverse,
Three of these pieces of information are particularly important in the cabin pressure control system: altitude corrected according to barometric pressure, absolute altitude, and their barometric correction. When controlled by the CPU 54, absolute altitude information is obtained, the pressure difference between the pressure outside the aircraft and the pressure inside the aircraft is monitored and adjusted to obtain a suitable rate of change in the cabin pressure as a function of the planned altitude of the airplane. need to be determined. Also, using the altitude corrected according to the atmospheric pressure, 0PUS4 determines the cabin pressure necessary for the preparation.

0PU 54 decodes the identification code of the data word input from data input circuit 116 and determines whether such data word is appropriate for operation of the cabin pressure control system.

If the input data word is correct, 0PU 54 stores the candy and calculates a new rate of change in cabin pressure. After memorizing the arta language, the CPU 54 sends a 7-dress decoder 120
A reset signal is sent to the reset input terminal of the data input circuit 116 via the terminal 3 of the data input circuit 116, and the data input circuit 116 further receives a signal from the multiplexer 10B to be in a memorizable state.

When the CPU 54 cannot perform foreground work in a predetermined period, a decoder enable signal is input from the 0PU 54 via the output terminal l of the address decoder 121, and the one-shot multivibrator 141 performs input/output operations. Input terminal MR
The shift-or-ground job is enabled by the 0PUS4 until the set time in the one-shot multivibrator 141 ends.

As is clear from the above, FIGS. 2 and 3 show in detail the function of the circuit shown in FIG. 1. In order to change the internal pressure, the CPU 54 controls the predetermined rate of change P of the internal pressure. When the voltage vVA corresponding to oK is calculated and a trigger signal is sent from the output terminal 2 of the output buffer 113 to the sample holding circuit 98, the sample holding circuit 981C reads the output signal from the inverter 96 and holds the corresponding output signal for a predetermined period of time. Hold. Is the signal representative of a predetermined rate of change in the cabin pressure passed from the sample holding circuit 98 through the filter circuit 140'? 0 is sent to channel 0H-6 of analog multiplexer 56 and amplifier 144. On the other hand, the adder circuit 30 receives the output signal of the amplifier 144, the output signal BOA of the amplifier 34, and the output signal from the amplifier 146 as an offset voltage obtained by amplifying the output voltage VRIF from the reference voltage source 65.

The adder circuit 148 also calculates a predetermined rate of change of the cabin pressure signal. ,
and the voltage VRu, and outputs a signal representing the actual rate of change of the internal pressure changed by the voltage "RIP" to the buffer amplifier 150. The buffer amplifier 150 sends the output signal P.AB to the channel 0H of the analog multiplexer 56. -7 input.

A signal representing the difference between the predetermined rate of change and the actual rate of change in the internal pressure is sent from the adder circuit 30 to the adder circuit 38 via the lead/lag compensation circuit 156. On the other hand, the speed demodulation circuit 44 has
An energizing voltage of 115 V from a power supply 60 and signals τ, 0 and TAOHLO from a tachometer 40 (see FIG. 1) are input.

The amplifier 79 amplifies the output signal from the speed demodulation circuit 44 and inputs it to the addition circuit 381C. Summing circuit 38 generates a speed error signal for controlling the operation of drive motor 42 (not shown).

FIG. 2 also shows details of the valve open switch 48 and valve close switch 50 of FIG. A speed error signal is inputted from the error amplifier 46 to the first and second threshold circuits 152 and 154K. Threshold circuit 152 outputs the digital signal to AND gate 156, while threshold circuit 154 outputs the digital signal to AND gate 158, respectively. Also, the MD gate 156°158 has 0
A drive enable signal is inputted from the FT) 54 via the output terminal 4 of the output terminal 7A 113. Threshold circuit 152i,
When the positive speed error signal rises to a predetermined level, for example 1.257, the output level of the threshold circuit 152 is switched from low to high, and the positive speed error signal decreases to a predetermined level, for example 1.057. When threshold circuit 1
The output level of 52 is configured to switch from high to low.

On the other hand, the threshold circuit 154 switches the output level of the threshold circuit 154 from low to high when the negative speed error signal drops below a predetermined level, for example, -1.25V.
Also, the negative speed error signal is set to a predetermined level, for example -1.05V.
The output level of the threshold h-value circuit 154 is switched from high to low when the h-value circuit 154 rises above this level. MND
When 156 inputs a high level signal from threshold circuit 152 and a drive enable signal from 0PU54, AN
The D gate 156 outputs a command signal for opening the valve to the input terminal 5 of the input buffer 103 and the relay 160 made of a semiconductor. Relay 160 has an electro-optical configuration that does not respond to inappropriate inputs.

Relay 168, on the other hand, is largely controlled by relay drive logic circuit 134. That is, when the relay 16g is in the on position, a voltage that opens the valve is transmitted from the relay 168 to the drive motor 42 shown in FIG. Sent. The input terminal of converter 172 is connected to relay 160 and leader resistor 170Vc, and the valve open DC signal from converter 172 is sent to channel 0R-8 of analog multiplexer 56.

158 closes the valve by the input buffer 1030 input terminal 6 and another relay 174 composed of a semiconductor motor when a high level signal from the threshold circuit 154 and a drive enable signal from the OPU are input. Outputs a command signal to This is K, shibreader resistor 1
A circuit consisting of a relay 174 connected in parallel with 82 sends a suitable voltage from relay 168 to drive motor 42 (see FIG. 1) to close the valve. The input terminal of the converter 184' is connected to the relay 174 and the bleeder resistor 182, and the analog DC output signal from the gam/D converter 184' is sent to channel 0H-9 of the analog multiplexer 56.

As shown in Figure 3, 1 data mother! Output from 0PU54 via data buffer amplifier 88 on I85
Output buffers 113 and 184 each have 8-bit data terminals 0-7 for controlling each component of the cabin pressure control system. 0PU
Under the control of 54, outputs 7a 113 and 184 are activated using digital write signals from output terminals 4.5 of address decoder 120, respectively. Output x7a11
The data bits from output terminals 0 and 1 of 3 are used during bench test mode of the cabin pressure controller. Further, data signals from the output terminals 2, 4, 5.7 of the output sofa 113 are used in the manner described above in connection with the circuit operation of FIG. On the other hand, in the illustrated embodiment, the output terminal 3 of the output terminal 7A 113 is a spare terminal, and the output signal of the output terminal 6 indicates whether the valve 52 of FIG. 1 is in the closed or open state.

The display panel 186 shown in FIG. 4 is controlled by the data bits of output terminals 0 to 7 of the output terminal 77184. Data bits from output terminals 0-7 each cause an indicator light 187. to indicate a selector failure. Indicator light 188 indicating power off.
Indicator light 189 indicates a failure in the control circuit. Indicator light 190 indicates a failure in the gear. An indicator light 191 indicates a low inflow amount, an indicator light 192 indicates a drive motor failure, an indicator light 193 indicates a no-fault state, and an indicator light 194 indicates a confirmation mode.
sent and displayed.

Referring again to FIG. 2, a digital signal to be sent to the 0PU 54 is input to the input terminals θ to 7 of the human power input terminal 7A 101. More specifically, input terminal 0 receives a no-failure signal from output terminal 6 of output buffer 184 in the self-test mode to confirm the operation of the input/output terminals of this device. An automatic failure signal for confirming a series of operations by each frame, fault removal, and activation relay of the 7 lip-flops 12g to 128 in the self-test mode is input to the input terminal 1. The state of the indicator light 20g on the display panel 186 (see FIG. 4) of the OPU 54K is also monitored using the automatic failure signal. On the other hand, the signal input from the self-test switch 196 of the display panel 186 to the input terminal 2 is used to start the built-in test sequence. A glue set signal is input from the reset switch 197 of the display panel 186 to the input terminal 3 of the manual buffer 701. In addition, input terminals 4 and 5 each have
Signals from confirmation switch 198 and display panel 186
A signal from the press test switch 199 is input. Furthermore, the input terminals 6 and 7 have outputs 7 and 11, respectively.
A drivable signal for performing an operation test within the present device and an output signal from the D/D comparison circuit Zoo are inputted from the output terminal 4 of 3.

On the other hand, a no-fault signal is input to the input terminal OK of the input pan 77102 from the indicator light 193 indicating that there is no fault. Also, input terminals 1 to 6Ka, signals from valve 52 (see Figure 1), signals from confirmation switch 198 connected to relay 1681C, - signal indicating lowering by manual control, whether the device is in automatic control mode. An automatic enable signal, a landing gear signal, and a door close signal indicating whether or not the vehicle is in use are input, respectively. An interrupt signal for interrupting the operation of the 0PU 54 is input from the data input circuit 116 to the input terminal 7 of the input buffer 1020 .

By selecting the signal input to the input terminal 7 of the input buffer 102, it is determined by the 0PU 54 whether an interrupt signal has been sent from the data input circuit 116.

A signal DAO1 for partially testing the D/M converter 28 is inputted from the ratio soft circuit 97 to the input terminal 0 of the human power converter 7a 103. The input signals to the input terminals 1 and 5°6.7 are as described above. In the case of this embodiment, input terminals 2 and 3 are spare terminals, and input terminal 4
A no-fault signal is input from an indicator light 193 indicating that there is no fault.

According to the misfiring IIAK, there are two modes for controlling the valve 52;
That is, automatic mode and manual mode are available. When in automatic mode, valve 52 is positioned according to a program that controls the cabin pressure in response to sensed cabin pressure. On the other hand, in the manual mode, as shown in FIG. 4, the flow rate from the valve 52 is manually adjusted by the manual operation knob 201 on the display panel 186.

Also, the altitude selector 202 of the display panel 186
1ooo ~ + 15,0007 e) (approximately -3
A landing runway altitude within the range between 05 and +4580 m) is selected. On the high-resolution tape display 204,
The altitude selected by the altitude selector 202 is displayed.

Additionally, the selector 206 on the display panel 186 selects a range of 3G-1200 feet above sea level (approximately 9 to 6 cm) for the descent and a range of 50 to 2,000 feet (approximately 15.0 to 610 m) above sea level for the ascent. This selects the maximum rate of altitude change for the airplane over the range. Display device 208
is lit when an automatic failure signal is generated from 0PU54.

Indicator 212 on display panel 186 indicates the position of valve 52. Further, the mode selector 214 can be used to select either automatic mode or manual mode, and the internal pressure can be adjusted. When in manual mode, the pilot can use manual operating knob 201 to control the position of valve 52 to adjust the flow rate. On the other hand, in the automatic mode, one of the two cabin pressure control devices 10 controls cabin pressure in the manner described above, while the other is placed in a standby state, in which case all input signals necessary for controlling cabin pressure are manually input. However, unless one of the in-machine pressure control devices 10 breaks down, the other one is configured not to send a control signal to the drive motor 42.

In accordance with the present invention, the only actions required by the pilot in automatic mode are to select the landing runway altitude and to achieve the maximum rate of change of cabin pressure before takeoff. There is no need to change during the flight unless the destination is changed. According to the present invention, cabin pressure is controlled according to an automatic schedule showing a group of curves showing the relationship between cabin altitude (pressure) of an airplane and airplane altitude. An example of such an automatic planning table is shown in FIG.

According to FIG. 5, passengers feel extremely comfortable because pressure changes in the cabin are kept low independent of changes in the altitude of the airplane. For a given airplane, the actual cabin altitude (pressure)
The plan is to create a minimum rate of change in cabin altitude (pressure) corresponding to the airplane's theoretical maximum rate of climb while the airplane climbs toward maximum altitude. When in automatic mode, the cabin altitude (
The rate of change of altitude (pressure) is determined by the lesser of the altitude (pressure) rate of change value in the automatic planning table and the predetermined limit value of the altitude (pressure) rate of change; (approximately 152 m) and descending total @, 6 aoo feet (approximately 91! II), the latter numerator i, j 300 feet (
It is controlled according to the value of approximately 91 m).

According to the present invention, the cruising altitude is controlled, and the apparent upper cabin altitude (pressure) indicated according to the atmospheric pressure in the cabin is kept constant during cruising, and changes in cabin altitude (pressure) are kept within a predetermined range. . That is, when it is detected that the rate of change of the airplane altitude over a predetermined period of time exceeds a predetermined value (in feet) of the fraction, the cabin altitude (pressure) is automatically scheduled to reach a predetermined cabin altitude (pressure). Fixed. A predetermined cabin altitude (pressure) is maintained until the airplane is ascended or descended SOO feet from the altitude at which cruise is controlled, or until the difference between cabin and external pressures reaches a predetermined critical level. It will be done. To determine when the airplane has reached cruising altitude, it typically takes 500 feet (approximately 1521!1
) is preferably used as the reference value. The cruising altitude of the airplane fluctuates and is ±500 from the altitude at which cruise control is required.
feet (approx. ±152 m), the CP
Under the control of U54, the fixed cabin altitude (pressure) is released and the cabin altitude (pressure) is raised or lowered at a predetermined rate of change. An airplane flies at 1,000 feet (approximately 30 feet) per minute.
When descending by more than 4 m), the descending logic in the 0PU 54 is activated, while the logic associated with the autoplanning table is deenergized.

When the 0PU 54 receives a landing gear signal representing flight from the human power bag 77102, the autoplan command circuit and cruise control logic are energized. The predetermined cabin altitude (pressure) shall be the greater of the automatic plan value and the landing roll altitude, unless overridden by circuits that function to prevent excessive differences between cabin and exterior pressures. value is used.

The cabin altitude (pressure) value based on the automatic planning table is set so that, for example, the airplane can ascend rapidly while keeping the difference between the inside and outside pressures at a predetermined level. Since an airplane can climb more quickly with less payload, the pilot may choose a cabin altitude with a climb limit different from the airplane's actual rate of climb, in which case 0P.
U54 has the function of maintaining the differential pressure within the limit so that the rate of change of the pressure difference between the inside and outside of the machine does not exceed a predetermined value.

When the airplane starts taxiing until t when the airplane fuselage door is opened, the valve 52 is fully opened and no power is supplied.

Therefore, the cabin altitude (pressure) is approximately equal to the external pressure regardless of the amount of inflow introduced into the cabin.

Referring to FIG. 6, when the door is closed, the pressure drops through the valve 52, so that the normal cabin altitude (pressure) is, for example, 40 feet (approximately 12.2 m), which is smaller than the runway altitude.
is reduced to the value of Moreover, the cabin altitude (pressure) just before takeoff is still 150 feet (approximately 45 feet), which is smaller than the runway altitude.
The distance varies by a fraction of 300 feet (approximately 91.4 m), up to a level where it reaches a height of 7 m. After departure, the air pressure in the cabin is reduced by a fraction of 9,500 feet (approximately 152 m) until the cabin altitude (pressure) is controlled by the above-mentioned cruising altitude logic circuit.

The operation of the automatic control logic circuit and automatic planning circuit will be explained using a typical flight from Los Angeles to Chicago, which takes off and lands at sea level.

Referring to Figure 7, for a flight from Los Angeles to Chicago, the runway altitude was 126 feet (approximately 38.4 feet).
37.00 in 17 minutes after taking off from Los Angeles at
Climb to an altitude of 0 feet (approximately 11,300 m), maintain that altitude for a while, and then climb another 42,000 feet (approximately 12,000 m).
800m) in 7 minutes and reached an altitude of 43.00m.
We cruised for about 3 hours at 0 feet (approx. 13,100 m), then descended in 15 minutes to an altitude of 20,000 feet (approx. 61,003!L);
It maintained an altitude of 100 m (100 m) for 5 minutes and then descended to an altitude of 666 feet (approximately 203 m) in 10 minutes. Pilots do not need to select a landing altitude of 666 feet (approximately 203 m) before takeoff and reset it during flight.

On the other hand, during takeoff, the cabin altitude (pressure) increases at a rate of approximately 31 feet (approximately 116 m) according to the automatic schedule. The cabin altitude (pressure) is maintained at the value specified in the planning chart during the aircraft altitude of 37°,000 feet (approximately 11,300 m).
Next, the plane is 37,000 feet (about 11,300 m)
As the aircraft ascends to 42,000 feet (approximately 12,800 m), the cabin altitude (pressure) is again increased at a rate of approximately 230 feet (approximately 70.0 m) in accordance with the values specified in the schedule. The plane was at an altitude of 42°,000 feet (
The cabin altitude (pressure) during cruising was approximately 12,800 m) and 800 m.
It is maintained at a cruising altitude (pressure) of 0 feet (approximately 2440 m).

When the plane descended 1,000 feet (approximately 305 m), passengers! Altitude (pressure) is automatic planning table value and landing altitude 666
feet (approximately 203 m). The rate of decrease in the values in the planning table is 3 above sea level.
Above 00 feet, the cabin altitude (pressure) is reduced at a rate limited by that value. The plane was at an altitude of 20,000 feet (approximately 61
00 m), the cabin altitude (pressure) continues to decrease at a rate proportional to the limit, reaching the schedule value when it reaches 42,000 feet (approximately 12,800 m).

When the plane descends again, the cabin altitude (pressure) fraction #)s
The cabin altitude (pressure) decreased at a rate of approximately 220 feet (approximately 67.1 m) according to the plan, and the cabin altitude (pressure)
(48 m) (landing altitude) small 80 ft (approximately 24 m)
．． 4 m) much larger) reaches K. Passenger car altitude after landing (
The pressure increases by a fraction of 9600 feet until valve 52 is fully opened.

During such a flight, the pilot does not have to adjust the device of the invention, and the rate of change of cabin altitude (pressure) is maintained within a range comfortable for the passengers.

The embodiments of the present invention are summarized as follows.

(1) A device that generates a landing altitude signal indicating a predetermined landing runway altitude, a device that generates a rate of change signal that indicates a predetermined maximum allowable rate of change in cabin air pressure, and the landing altitude signal and the rate of change signal. an air pressure control device that responds to the air pressure and maintains a predetermined relationship between cabin air pressure and external pressure.
4° (21) a device for detecting an actual rate of change of gas pressure in a closed space; a device for generating a rate of change error signal expressed as a function of said actual rate of change of gas pressure and a predetermined rate of change; and a device for adjusting the gas flow rate in the closed space in response to a rate of change error signal to maintain the actual rate of change at the predetermined rate of change.

(3) Arrival at Pj! setting a runway altitude selector to generate a landing altitude signal indicative of a predetermined landing altitude; and setting an automatic rate of change limit selector to indicate a maximum rate of change indicative of a predetermined maximum permissible rate of change in cabin air pressure; a step of generating a signal, a step of measuring the air pressure in the cabin, a step of generating an actual rate of change signal indicating the actual rate of change of the air pressure in the cabin, a step of inputting a signal indicating the external pressure, and the step of landing. A method for controlling air pressure in an aircraft comprising the steps of adjusting the position of a valve in response to an altitude signal, an actual rate of change signal, a maximum rate of change signal, and external pressure.

[Brief explanation of the drawing]

Figure 1 is a simple block diagram of an embodiment of the in-flight pressure control system using unexploded FIAK, Figures 2 to 2C are detailed diagrams of the block diagram in Figure 1, and the third quotient is the OPU in Figure 2B. A block diagram showing the status of input/output signals by function, Figure 4 is 2A.
A front view of a display panel used in the apparatus shown in Figures to Figures 2C;
Figure 5 is a graph as a flight plan chart showing the relationship between cabin altitude and airplane altitude, Figure 6 is a graph showing changes in cabin altitude (pressure) until the airplane door is closed and takeoff, and Figure 7 is a graph of the airplane. It is a graph showing an example of an altitude plan and a cabin island degree plan accompanying it. DESCRIPTION OF SYMBOLS 10... Cabin pressure control device, 12... Mode selector, l9... Logic circuit, 20... Cabin pressure sensor, 22
...bamboo converter, 26...limiting circuit, 28...
D/A converter, 30... Adding circuit, 32... Analog differentiator, 34. 36... Amplifier, 38... Adding circuit, 40... Tachometer, 42... Drive motor, 44... ...speed demodulation circuit, 46...error amplifier,
48... Valve open switch, 50... Valve close switch, 52... Valve, 53... Standby control circuit, 54...
C! PU, 56...Analog multiplexer, 5
8... Adder, 60... Power supply, 62... Voltage divider,
64... Filter, 65... Reference voltage source, 66...
・Amplifier, 68... Voltage divider, 70... Filter, 7
2...Switch, 74.76...Resistor, 78...
・Adder, 79°82.83...Amplifier, 84...
Voltage drop monitoring circuit, 85...Data bus, 86...
Latch circuit, 88... data buffer amplifier, 90...
...Addition circuit, 92...Buffer amplifier, 94...
Amplifier, 96... Inverter, 97... Comparison circuit,
98...Sample holding circuit, ioo...Bamboo comparison circuit, 1
01, 102, 103... Input x7a, 104
...address decoder, 108...multiplexer,
110°112...Air data computer, 113
...Output buffer 7.116...Data input circuit, 1
17... OR gate, 118... 7 rigs, 120, 121... address decoder, 126...
...Time frame generator, 128°130"...
Flip 70 knob, 134... Relay drive - logic circuit,
136... Reset circuit, 138... One/Yoto multivibrator, 140... AND gate,
140...Filter circuit, 141...One shot multipipe rake, 144, 146...Amplifier, 148...Addition circuit, 150...Buffer amplifier, 152, 154...Threshold circuit , 156 , 1
58...Lead/lag compensation circuit, 160°168...
Relay, 170...Preader resistor, 172...'/
D converter, 174... Relay, 182... Leader resistor, 184... Output buffer, 186...
Display panel, 188°190, 192, 193,
194... Indicator light, 196... Self test switch, 197... Reset switch, 198... Confirmation switch, 199... Press test switch, 201...
...Manual operation knob, 202...Altitude selector, 204
... Tape indicator, 206 ... Selector, 208
, 212... Display H1214... Mode selector,
19.4'...Al1) Con/Guta TTG, 4- L Kun G-5 F'T/7;-7""'-'

Claims (1)

[Claims] (1) Detecting the actual rate of change in the pressure in the closed space;
comparing the detected actual rate of change with a predetermined rate of change to generate a rate of change error signal; and adjusting the air flow rate in the closed space in response to the rate of change error signal to adjust the actual rate of change to the predetermined change rate. A closed space air pressure control method comprising: (2) a first device that generates a first signal indicating a rate of change in the atmospheric pressure in the closed space; and a second device that generates a second signal indicative of a predetermined rate of change in the atmospheric pressure in the closed space; a third device for generating an error signal represented as a function of the difference between the first signal and the second signal; and a third device for adjusting an air flow rate in the closed space in response to the error signal; A pneumatic pressure control device for controlling the air pressure in a closed space, comprising: a fourth device that maintains the air pressure inside and the actual rate of change of the air pressure at a predetermined value. (3) The first device includes a pressure sensor device that generates a pressure signal indicating the actual atmospheric pressure in the closed space and a device that generates an actual rate of change signal that is proportional to the rate of change of the actual atmospheric pressure in the closed space. An air pressure control device according to claim 2, comprising: (4) The air pressure control device according to claim 3, comprising an amplification device for amplifying the actual rate of change signal. (5) The second device includes a calculation device, an external pressure signal generation device connected to the calculation device and providing a signal indicating the external pressure to the calculation device, and a pressure signal generator connected to the calculation device that generates a pressure signal and an actual rate of change. a multiplexer device for inputting any one of the signals, and a pressure signal generating device for supplying an output signal from the computing device to a third device, the computing device computing a predetermined rate of change of the pressure signal. 4. The air pressure control device according to claim 3, wherein the air pressure control device is arranged to maintain a predetermined relationship between the actual air pressure in the closed space and the external pressure of the machine. (6) The external pressure signal generator includes a data input device that inputs and stores a signal indicating flight data, and outputs an input signal after storing the flight data signal, and a data input device that is connected to the data input device and responds to the input signal. and an OR gate for supplying an interrupt signal to a computing device to interrupt the operation of the computing device and causing the computing device to read the flight data signal stored in the data input device. The pneumatic control device according to item 5. (7) The air signal generating device includes a D/A converter connected to the first output terminal of the computing device, and the D/A':
a sample holding circuit connected to a second output terminal of the first sampler; and the D/A connected to a third output terminal of the computing device and configured to be able to send a trigger signal to the sample holding circuit.
and an address decoder device for sampling and holding the output of the D/A converter via the sample holding circuit when the output of the converter represents a predetermined rate of change in atmospheric pressure. The pneumatic control device according to item 5. U3) The error signal generating device includes a first addition circuit, and the first addition circuit has a first input terminal connected to the amplifier device, a second input terminal connected to the sample holding circuit, and a closed space. 8. The pneumatic pressure control system of claim 7, wherein the output signal is expressed as a function of the difference between an actual rate of change and a predetermined rate of change in the air pressure within the air pressure system. (9) The fourth device includes a valve, a drive motor connected to the valve, a power supply device that supplies power to the motor, and controls the power supply to the motor to control the position of the valve. 9. The air pressure control device according to claim 8, further comprising a valve position adjusting device for adjusting the air pressure. A tachometer device that generates a motor speed signal representing the speed of the QO motor; summing device, wherein said @2 summing circuit is arranged to generate a motor speed error signal proportional to the difference between the air signal and said motor speed signal.
Pneumatic control device as described in section. A συ electric power supply device includes a power source, a relay connected between the power source and the motor, and a computing device that switches the relay between an energized position and a deenergized position to supply power to the motor. 11. The air pressure control device according to claim 10, further comprising a logic circuit that can be supplied to the air pressure control device. The α2 valve position adjustment device includes an error amplifier connected to the output terminal of the second adder circuit to generate a motor drive signal, and an error amplifier connected to the error amplifier to generate an output signal when the motor drive signal exceeds a predetermined value. a first threshold circuit connected to the error amplifier and generating an output signal to close the valve when the motor drive signal is less than a predetermined value; 10. The pneumatic pressure control device according to claim 9, which includes a value circuit. Q3: a first AND gate whose first and second input terminals are respectively connected to the output terminal of the first threshold circuit and the calculation device and input a drive enable signal; 13. The pneumatic control device according to claim 12, wherein the terminals each include a second threshold circuit and a second AND gate connected to the calculation device and inputting a drive enable signal.