JPH04201771A - Automatic brake device - Google Patents

Abstract

PURPOSE:To simultaneously attain brake operation of comfortable riding and shortening of a braking distance and time by inputting an airframe speed signal to a control unit, and changing a target deceleration rate by a preset function in accordance with an airframe speed. CONSTITUTION:An aircraft automatic brake device is constituted by changing partly a controller, built in a control unit 2, that is, a set deceleration rate indication signal part. That is, applied speed voltage is voltage-compared in comparators 11 to 13 to select a deceleration rate through an analog multiplexer 14, and for obtaining a required brake pressure in an operation amplifier 10, a required error signal is transmitted. In this way, the target deceleration rate is changed by an airframe speed to obtain a smooth brake, and a braking distance and time are shortened while improving comfortableness to ride.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an improvement of an electronically controlled autobrake device, in which the deceleration rate is controlled by an arbitrary free curve according to the aircraft speed, unlike the conventional constant deceleration rate control method. An autobrake system for aircraft and high-speed railway vehicles that can simultaneously achieve so-called comfortable braking operation and shorten braking distance and braking time by using an aircraft speed-sensitive deceleration rate control method that changes based on the expressed functional relationship. Regarding.

BACKGROUND OF THE INVENTION For example, the configuration of an electronically controlled autobrake system for aircraft, as shown in FIG. So,
Based on the deceleration rate from the sensor (3) and the wheel rotation speed signal from the rotation speed sensor (8) of the wheel (6), the required calculated control signal is used to control the pressure oil from the hydraulic source (4). output to a hydraulic control valve (5) such as an electro-hydraulic servo valve or solenoid type on-off valve, and
The brake system (7) is configured to control the necessary brake pressure oil to be sent to the brake device (7).

The automatic braking system depends on the length of the runway, wind direction, wind speed, weather conditions, especially whether it is raining, sunny, or snowy, as well as aircraft speed, landing weight, etc. One set deceleration rate is selected by the selection switch on the control panel (1).

To explain the operation in detail, the control device (2) of the autobrake device
) is the aircraft deceleration rate calculated from the rotation speed signal of the wheels (6), or the direct sensor (3), so that a constant set deceleration rate corresponding to the command signal selected by the operator is obtained.
The brake pressure is adjusted so that the difference between the aircraft deceleration rate measured at and the selected set deceleration rate becomes zero.

In this case, if a deceleration rate larger than the deceleration rate expected from the road surface friction force is set, automatic brake control becomes impossible. That is, skid occurs before the set deceleration rate is reached, and autobrake control is overridden by antiskid control, making autobrake control impossible.

When a skid occurs, brake pressure is applied and released cyclically, reducing ride comfort for passengers, etc. Therefore, pilots usually select a set deceleration rate that is lower than the required deceleration rate and perform anti-skid control. In other words, priority is given to brake operation that provides a comfortable ride.

Problems to be Solved by the Invention The above-mentioned braking operation that provides a comfortable ride requires setting the deceleration rate below the maximum deceleration rate that can be obtained at high speeds, and the advantage of increasing the maximum deceleration rate as the speed decreases is lost. You don't get it.

Generally, the maximum coefficient of friction between the contact surface between the road surface and the wheels decreases as the vehicle speed increases under the same road surface conditions, as shown in FIG.

When selecting a deceleration rate based on these facts, the operator should set the maximum expected deceleration rate at the current speed, for example, as shown in Figure 3, so that ride comfort can be prioritized and the brakes can be operated smoothly. Select a constant deceleration rate that is lower than the deceleration rate.

For this reason, although smooth deceleration is possible, as the speed decreases, the difference between the set deceleration rate and the maximum deceleration rate obtained from the maximum friction coefficient of the road surface becomes wider, allowing for smooth brake operation and shorter stopping distances. Shortening is a contradictory condition.

In view of the problem that the braking distance of the brake increases in order to give priority to brake operation with a comfortable ride in electronically controlled autobrake devices for aircraft and high-speed railway vehicles, this invention has been developed to provide so-called brake operation with a comfortable ride. The object of the present invention is to provide an autobrake device for aircraft and high-speed railway vehicles that has a configuration that can simultaneously shorten braking distance and braking time.

Means for Solving the Problems This invention provides a control device that uses a set deceleration rate selected by an operator on a control panel;
Adjust the pressure oil from the hydraulic source to the wheel brake system at a constant deceleration rate so as to eliminate the difference between the aircraft deceleration rate calculated from the wheel rotation speed signal and the aircraft deceleration rate measured by l or the direct sensor. In an autobrake system that controls a hydraulic control valve for a vehicle, the control device uses a control device that manually inputs the aircraft speed signal from the speedometer to the control device to change the target deceleration rate according to a preset function according to the aircraft speed. This is an autobrake device characterized by being installed in a.

Operation This invention controls the target control law at a constant deceleration rate (straight line 4) at a value lower than the conventional maximum deceleration rate (curve A) expected at the current speed as shown in Figure 3. From the method, as shown in Figure a, there are polygonal lines (curve 1) and straight lines (straight line 2).
), and various other functional relationships represented by arbitrary free curves (curve 3), the deceleration rate can be changed according to the aircraft and vehicle speed, allowing smooth braking operation and shortening of braking distance and braking time at the same time. It is something to be achieved.

The automatic brake system for aircraft and high-speed railway vehicles according to this invention can effectively utilize the frictional characteristics of the road surface by making the target deceleration rate variable depending on the aircraft and vehicle speed, allowing smooth brake operation similar to conventional control methods. In addition, the stopping distance and time can be shortened compared to conventional methods.

In this invention, various functions expressed by arbitrary free curves for changing the deceleration rate according to the aircraft and vehicle speed are determined based on the length of the runway, wind direction, wind speed, weather, especially whether it is raining, Multiple types of functions can be set in advance according to various conditions such as whether it is a clear sky or snowy surface, aircraft speed, aircraft landing weight, etc. so that the pilot can select from the selection switch on the control panel in the cockpit. .

For this setting, the preferred function and control method are:
For example, if the braking force is set in stages of minimum, medium, and maximum, and the aircraft and vehicle speeds are 1100 k/hr, the target deceleration rates are set to 0.2 g, 0.43 g, and 0.04 g, respectively.
When set to 4g, when the speed is 300km/hr, the values will be 0.1g, 0.2g, and 0.3g, respectively.
A function that lowers the target deceleration rate as the speed increases,
A control method can be adopted.

If the control device is an analog control device, the conventional configuration can be used by changing or adding some circuits.

If the control device is digitally controlled, it is even easier.
The set deceleration rate can be easily applied by making it dependent on airframe and vehicle speed data and pre-programming it into a desired curve or functional relationship.

Further, the present invention can be applied to automatic deceleration and stopping devices for general vehicles in addition to automatic braking devices for aircraft and high-speed railway vehicles, and can also be applied to automatic decelerating and stopping devices for other general industrial equipment.

Embodiment FIGS. 4 and 5 are circuit diagrams showing an example of a control device used in an aircraft autobrake system. FIG. 4 is a circuit diagram of a control device according to the present invention, and FIG. 5 is a conventional circuit. It is a diagram.

The aircraft autobrake system according to the present invention uses the conventional configuration shown in FIG. It consists of:

When the deceleration rate instruction control law of the control device (2) is configured with an analog circuit, the set deceleration rate is usually as shown in FIG.
It consists of a constant voltage circuit using a Zener diode and a voltage divider circuit using an appropriate resistance, and as the deceleration voltage is applied, the necessary error signal is generated by the operational amplifier (1o) to obtain the required brake pressure. Sent.

The control law circuit of the present invention uses a speed voltage that defines the magnitude of the speed to appropriately select a plurality of prepared voltage dividing circuits depending on the speed voltage, thereby achieving aircraft speed-sensitive deceleration. The rate control method is realized.

That is, the applied speed voltage is converted to the comparator Ql)(
12) The voltages are compared in (13), the deceleration rate is selected via the analog multiplexer (14), and the operational amplifier (
At step 10), the required error signal is generated in order to obtain the required brake pressure.

With the control device (2) having such a circuit, the target deceleration rate can be changed depending on the speed of the aircraft, smooth braking is achieved, the ride is comfortable, and the braking distance and braking time are shortened.

The speed-sensitive deceleration semi-control system control device according to the present invention, especially when applied to deceleration at high speeds of 300 km/hr or more, provides smooth braking, provides a comfortable ride, and shortens braking distance and braking time. Ru.

Effects of the Invention The autobrake device for aircraft and high-speed railway vehicles according to the present invention changes the deceleration rate from the conventional fixed deceleration rate control method to the speed that changes the deceleration rate according to a functional relationship expressed by an arbitrary free curve according to the speed of the aircraft and vehicle. By using the sensitive deceleration semi-control system, it is possible to simultaneously achieve so-called smooth braking with good riding comfort and shortening of braking distance and braking time.

The present invention has the advantage that conventional hardware can be used in an analog-controlled autobrake system for aircraft, etc. by changing or adding some of the hardware circuits, as in the embodiment.

Furthermore, in an autobrake device for an aircraft or the like that employs digital control, conventional hardware can be used as is by changing some of the control software without changing the hardware.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration and control method in which the present invention is applied to an aircraft autobrake system. FIG. 2 is a graph showing the relationship between aircraft speed and maximum friction coefficient. FIG. 3 is a graph showing the relationship between the speed of the aircraft and the deceleration rate, and FIG. 3A shows the case of the present invention, and FIG. 3 shows the conventional case. FIG. 4 is a circuit diagram of a control device according to the present invention. Fifth
The figure is a circuit diagram of a conventional control device. DESCRIPTION OF SYMBOLS 1...Control panel, 2...Control device, 3...Sensor, 4...Hydraulic pressure source, 5...Hydraulic control pulp, 6...
Wheels, 7... Brake device, 8... Rotation speed sensor, 10... Operational amplifier, 11, 12, 13... Comparator, 14... Analog multiplexer.

Claims (1)

[Claims] 1. A set deceleration rate selected by an operator on a control panel in a control device;
Adjusts the pressure oil from the hydraulic source to the wheel brake system at a constant deceleration rate so as to eliminate the difference between the aircraft deceleration rate calculated from the wheel rotation speed signal and/or the aircraft deceleration rate directly measured by the sensor. In an autobrake system that controls a hydraulic control valve for a vehicle, the control device inputs the aircraft speed signal from the speedometer to the control device, and controls the control device to change the target deceleration rate according to a preset function according to the aircraft speed. An autobrake device characterized by being installed in.