A zero-finding device for the limit turntable of the airport runway foreign object detection system

Abstract

The invention provides a zero-finding device for the limiting turntable of an airport runway foreign matter detection system. A limiting disc is arranged on the motor rotating shaft of a limiting turntable. A positioning ring and the limiting disc are absolutely coaxially and fixedly mounted. The positioning ring is not rotated along with the limiting turntable. The limiting disc is provided with a zero-finding start bit light slit and a zero-finding bit light slit along the radial direction of the limiting disc according to the zero-finding direction of the limiting turntable during the start-up process. A photoelectric switch is accurately positioned at a mechanical home position of the positioning ring and is maintained stationary. In this way, during the rotation of the limiting disc, the zero-finding start bit light slit and the zero-finding bit light slit successively and correctly pass through the light pillar of the photoelectric switch to trigger the photoelectric switch, so that an electrical signal is generated. According to the technical scheme of the invention, the photoelectric switch is accurately positioned at the mechanical home position of the positioning ring, so that the relative assembly error during the assembling process is reduced. Meanwhile, the limiting disc is provided with light slits, and the switch is triggered based on the light permeability of the light slits. Therefore, the zero-finding positioning accuracy is greatly improved. At the same time, the selection cost of the photoelectric switch is lowered.

Description

technical field [0001] The invention belongs to the technical field of limit turntable control of an airport runway foreign object (FOD) detection system of civil aviation, and in particular relates to a limit turntable for an airport runway foreign object (FOD) detection system that realizes high-precision search for mechanical zero when starting. zero device. Background technique [0002] With the rapid development of the world's civil aviation industry, the number of civil passenger aircraft has increased significantly, and the take-off and landing of airport flights have become more frequent. Aircraft damage, flight accidents and flight delays caused by foreign object debris (FOD) on the airport runway have occurred frequently. Rising, the degree of damage is increasing, and it has brought huge impact and loss to the civil aviation industry. At present, runway inspections at home and abroad mainly rely on runway inspectors to complete the walk inspection of the runway f...

AI Technical Summary

Problems solved by technology

The technical problem solved by this patent application is: the method of resetting the turntable angle of the photoelectric switch used in the past, because the working principle of the photoelectric switch will bring a large system error, if the reset accuracy is to be improved, the control program will be very complicated, and it needs to be set Only by judging with multiple criteria can the zero position be determined; and the complexity of the criteria not only increases the amount of calculation of the system, but also has too many program criteria, and it is also easy to make mistakes in the process of writing the control program

This patent application only determines the zero position through simple judgment. Although it can improve the reset accuracy, this method uses a collision method to achieve reset. Long-term operation may cause damage to the internal structure of the turntable transmission structure, motor, etc., and is affected by different rotational speeds. Due to the impact of collision, the accuracy of determining the zero position during normal operation is far from meeting the operating accuracy requirements of the limit turntable of the FOD system

[0006] The beam diameter of high-resolution photoelectric switches currently on the market is usually 0.5-1mm, and some manufacturers provide up to 0.1mm, but the price is expensive

If the calculation is carried out according to the 0.1mm light column, assuming that the effective diameter of the positioning ring of the motor shaft is about 20cm, the maximum error caused by the limit piece when triggered at different positions of the light column of the photoelectric switch can still reach about 0.0573 degrees. It is intolerable to ensure that the FOD system realizes the continuity of foreign object detection on the runway hundreds of meters away. In theory, if the diameter of the positioning ring is increased, the homing positioning accuracy of the turntable can be improved, but in fact, due to the design and installation size of the turntable, it is difficult Accuracy is improved by this

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