Pull-type aircraft refueling system

Abstract

The invention relates to a towed aircraft refueling system which comprises a refueling control device, an interlocking device, a hydraulic device and an electric control device. The refueling control device is installed on a pipeline refueling trailer and comprises a ground well hose connector, a ground well hose, a coarse oil filter assembly, an electromagnetic pressure control valve, a rotary connector, a flow control electromagnetic valve, a filter, a flow meter, a safety relief valve, a reel ball valve, a venturi tube, an oil conveying hose and a pressure refueling connecting nozzle which are sequentially connected. The ground well hose connector is used for being connected with a ground well valve on an airport apron so as to introduce aviation oil. The pressure refueling nozzle is used for being connected with an aircraft fuel tank inlet to complete refueling. The interlocking device is used for performing brake interlocking and refueling oil path interlocking control on the refueling control device; the hydraulic device is used for providing hydraulic driving force for a hydraulic execution component on the refueling trailer; the electric control device is used for providing a control circuit for the refueling control device. Compared with the prior art, the invention has the advantages of maneuverability, flexibility, easy operation, energy conservation, economy, safety, environmental protection and the like.

Description

Technical Field

[0001] This invention relates to the field of aircraft refueling equipment, and in particular to a towed aircraft refueling system. Background Technology

[0002] In recent years, with the rapid development of the civil aviation industry, the requirements for aircraft refueling support have become increasingly stringent, and the operating conditions of refueling equipment have become increasingly complex. Currently, refueling support at domestic transport airports mainly relies on pipeline refueling trucks and tank refueling trucks for refueling aviation kerosene at trunk and feeder airports. With the significant increase in flight volume, refueling trucks frequently shuttle within the airport, increasing the risk of collisions with aircraft.

[0003] Furthermore, the qualification requirements for aircraft pipeline truck refueling operators are that they must hold a B2 driver's license and obtain a civil aviation professional skills assessment certificate before they can work independently. Therefore, the requirements for refueling operators are relatively high.

[0004] The increasingly complex apron operation conditions in China necessitate the exploration of a new refueling model. Therefore, it is essential to research a non-powered, towed aircraft refueling system, whose flexibility, compact size, and reliable operation are better suited to the increasingly complex apron operation conditions of the future.

[0005] For example, invention CN114458661A discloses a towed oil pump truck system and control method, which includes a first oil supply system, a second oil supply system, and a third oil supply system for separately supplying oil to hydraulic systems 1, 2, and 3 of an aircraft; a purification system for purifying the oil in hydraulic systems 1, 2, and 3 of the aircraft; a dehydration system for removing water from the oil in hydraulic systems 1, 2, and 3 of the aircraft; and a refueling system for refueling hydraulic systems 1, 2, and 3 of the aircraft. This system can be used to provide the required hydraulic energy to hydraulic systems 1, 2, and 3 during routine aircraft maintenance, inspection, and troubleshooting, purify the aircraft hydraulic system, replenish hydraulic oil to the hydraulic system, and detect the contamination level and water content of the hydraulic oil.

[0006] Although the solution provides a towed oil pump truck system, it only proposes multiple oil supply systems and does not clearly indicate whether a large oil tank is not needed for pipeline refueling trailers. Furthermore, its control process is only a simple control of the hydraulic system oil, which cannot guarantee safety and efficiency. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a towed aircraft refueling system that is free from the space limitations of fixed refueling trucks and has the advantages of being mobile and flexible, easy to operate, simple to maintain, energy-saving and economical, safe and environmentally friendly.

[0008] The objective of this invention can be achieved through the following technical solutions: A towed aircraft refueling system includes a refueling control device, an interlocking device, a hydraulic device, and an electronic control device; The refueling control device is installed on the pipeline refueling trailer and includes, in sequence, a well hose connector, a well hose, a coarse oil filter assembly, an electromagnetic pressure control valve, a rotary joint, a flow control solenoid valve, a filter, a flow meter, a safety relief valve, a reel ball valve, a venturi tube, an oil delivery hose, and a pressure refueling nozzle. The well hose connector is used to connect to the well valve on the apron to introduce aviation fuel; the pressure refueling nozzle is used to connect to the aircraft fuel tank inlet to complete refueling. The interlocking device is used for brake interlocking and refueling circuit interlocking control of the refueling control device. The hydraulic device is used to provide hydraulic driving force for the hydraulic actuators on the refueling trailer; The electronic control device is used to provide control circuitry for the refueling control device.

[0009] Furthermore, the filter is equipped with a primary filter element, a secondary filter element, a filter drain pipe, a ball valve, and an automatic venting valve; the refueling control device also includes a recovery tank. Both the primary and secondary filter elements are located inside the filter, and the filter drain pipe is located at the bottom of the filter. When aviation fuel passes through the filter, solid particles are filtered out by the primary filter element, and water is filtered out by the secondary filter element. The filtered water is discharged through the filter drain pipe at the bottom of the filter. The ball valve is located on top of the filter, and the automatic venting valve is connected to the ball valve. When there is gas in the pipeline of the refueling control device, the gas is discharged through the ball valve on top of the filter and the automatic venting valve. The discharged gas and the aviation fuel carried out enter the recovery tank. The safety relief valve is located on top of the filter. When the pipeline pressure of the refueling control device exceeds the pressure threshold, the aviation fuel is released through the safety relief valve into the recovery tank.

[0010] Furthermore, the filter is also connected to a self-resetting valve and a closed-loop sampler, which is used to discharge the aviation fuel in the filter into the closed-loop sampler, and to detect the fuel condition of the closed-loop sampler by visual inspection or test paper. The filter is also equipped with piston-type differential pressure gauges at both the inlet and outlet ends to measure the pressure difference across the filter.

[0011] Furthermore, the oil drain port of the closed-circuit sampler and the outlet pipeline of the piston differential pressure gauge are both connected to a recovery tank for aviation fuel recovery. The recovered fuel tank is also connected to a fuel pumping system, which is equipped with a jet fuel pump. When the fuel level in the recovered fuel tank reaches a preset height threshold, the fuel pumping system is activated and the jet fuel pump transfers the aviation fuel in the recovered fuel tank to the front end pipe of the filter. After being filtered by the filter, the fuel is then added to the aircraft fuel tank.

[0012] Furthermore, the electromagnetic pressure control valve is controlled by the set pressure feedback signal measured in the venturi tube and the refueling control device. The pressure refueling nozzle is equipped with a pressure regulator. When the aircraft fuel tank is full and closed, the pressure regulator controls the electromagnetic pressure control valve to close, thereby controlling the static pressure and fluctuating pressure within the pressure refueling nozzle.

[0013] Furthermore, the interlocking device includes a brake interlocking module, which is used to unlock the brake structure of the pipeline refueling trailer after all the pull-out parts on the pipeline refueling trailer have been retracted and reset; otherwise, the pipeline refueling trailer is put into a braking state by hydraulic oil from the hydraulic device; the hydraulic drive pipeline of the brake interlocking module is connected to an emergency interlock release switch, which is used to release the braking state of the pipeline refueling trailer. The interlocking device also includes a Daedman module, which is communicatively connected to the electromagnetic pressure control valve and used to control the opening or closing of the oil circuit of the electromagnetic pressure control valve; the Daedman module is connected in parallel with an overriding Daedman module, which is used to control the electromagnetic pressure control valve through the overriding Daedman module when the Daedman module fails; the electromagnetic pressure control valve is also connected to a Daedman shut-off solenoid valve, which is used to cut off the control of the electromagnetic pressure control valve by the Daedman module and the overriding Daedman module.

[0014] Furthermore, the hydraulic device includes a well hose hydraulic control module, which includes hydraulic outriggers, a manual directional valve, and a well hose retraction mechanism. The hydraulic outriggers are multiple, and the hydraulic oil of the hydraulic device is connected to each hydraulic outrigger through the manual directional valve. Each hydraulic outrigger is connected to the well hose retraction mechanism to drive the well hose retraction mechanism to lift and lower. The well hose is installed on the well hose retraction mechanism. The hydraulic device also includes a brake drive module, which is used to supply oil to the brake structure oil circuit of the pipeline refueling trailer according to the brake signal. The hydraulic oil for the hydraulic device is supplied by an electro-hydraulic power unit.

[0015] Furthermore, the electronic control device includes an interlocking control module, which includes a controller and a controller power supply circuit. The controller is connected to an electromagnetic pressure control valve, a flow control solenoid valve, and a flow meter, respectively. The controller power supply circuit is powered by a regulated power supply. The electronic control device also includes a Daedman control module, which is used to control the Daedman module's circuitry. The corresponding control process includes: after the Daedman module is pressed open, the electromagnetic pressure control valve is opened and the refueling control device starts refueling; after the Daedman module is released, the electromagnetic pressure control valve is closed after a first delay; if the time for pressing open the Daedman module reaches a time threshold, a corresponding indicator light will flash to indicate this, and the electromagnetic pressure control valve will be closed after the flashing reaches a first time.

[0016] Furthermore, the electronic control device also includes a refueling ladder bracket lifting anti-collision circuit. The refueling control device also includes a refueling ladder bracket and a refueling ladder. The refueling ladder is installed on the refueling ladder bracket, and the refueling ladder bracket is connected to a lifting drive structure. The refueling ladder is equipped with multiple anti-collision switches. The refueling ladder bracket lifting anti-collision circuit is connected to the lifting drive structure and the anti-collision switches respectively. It is used to drive the refueling ladder bracket to rise when it receives a refueling ladder bracket lifting command; drive the refueling ladder bracket to descend when it receives a refueling ladder bracket lowering command; and trigger an alarm via the vehicle obstacle light and drive the pipeline refueling trailer to stop when it receives an anti-collision switch activation command.

[0017] Furthermore, the electronic control device also includes a radar ranging and early warning collision avoidance module. This module includes multiple ultrasonic radars and photoelectric switch sensors. The ultrasonic radars and photoelectric switch sensors are respectively installed on the left and right sides of the pipeline refueling trailer. The ultrasonic radars are used to measure obstacles within the effective detection range and issue audible alerts. The photoelectric switch sensors are connected to the collision avoidance system controller of the pipeline refueling trailer and are used to achieve different distance trigger signals by adjusting the photosensitive sensitivity. The radar ranging warning and collision avoidance module also includes a collision avoidance control circuit. The ultrasonic radar and photoelectric switch sensor are both connected to the collision avoidance control circuit. After the ultrasonic radar or photoelectric switch sensor triggers a signal, the collision avoidance control circuit controls the interlocking device to drive the pipeline refueling trailer to a stop or to drive below a preset low speed threshold.

[0018] Compared with the prior art, the present invention has the following advantages: (1) This invention proposes a non-powered pipeline towed aircraft pipeline refueling equipment. Through modular integrated design, multiple safety interlocking mechanisms and electromagnetic valve control of the fuel supply pipeline, it has the advantages of being mobile and flexible, easy to operate, simple to maintain, energy-saving and economical, safe and environmentally friendly. In the refueling control device, the core pump component is integrated on the towable pipeline refueling trailer to form a mobile refueling unit. It relies on the pressure of the apron well network for fuel supply and gets rid of the space limitation of fixed refueling trucks, which significantly improves the efficiency of flexible support for multiple aircraft positions on the apron. The refueling control device is equipped with a coarse oil filter component and a filter to achieve multiple filtration. Electromagnetic pressure control valve, flow control solenoid valve, flow meter, safety pressure relief valve and venturi tube are set to realize the detection and control of fuel supply pressure and flow, which is safer and more reliable.

[0019] (2) The filter set in the refueling control device of the present invention is first divided into a primary filter element and a secondary filter element to filter solid particles and water respectively. An automatic venting valve and a safety pressure relief valve are set at the top of the filter to discharge gas in the pipeline and release pipeline pressure to ensure the safety performance of the fuel supply pipeline. Furthermore, the automatic venting valve and the safety pressure relief valve are connected to the recovery tank for aviation fuel recovery, realizing the recycling.

[0020] (3) The interlocking device proposed in this invention is designed with an interlocking braking device for the working state of the pipeline vehicle, which can effectively prevent misoperation caused by the failure to fully retract the pulled-out part after the pipeline refueling device has finished refueling, and prevent the moving trailer from damaging the aircraft or facilities. On the other hand, an interlock control between the Daedman module and the electromagnetic pressure control valve is set up. The Daedman module realizes the on / off control of the electromagnetic pressure control valve. Alternatively, the Daedman of the electromagnetic pressure control valve can cut off the electromagnetic valve, thereby cutting off the control of the Daedman module on the electromagnetic pressure control valve and avoiding losses caused by a single control failure.

[0021] (4) The hydraulic device of the present invention uses four outrigger cylinders and a manual reversing valve. By operating the manual reversing valve, the well hose can be automatically retracted or extended, which is more convenient and reliable. Furthermore, the trailer brake can be controlled hydraulically, which can precisely control the braking force.

[0022] (5) The electronic control device provided by the present invention provides an interlocking control module to realize the power control and interlocking circuit control of the controller; a Dedemann control module to realize the refueling control of the Dedemann module; a refueling ladder bracket lifting anti-collision circuit to control the lifting drive structure of the refueling ladder and the refueling ladder bracket, and to set an anti-collision switch to alarm the vehicle obstacle; and a radar ranging early warning anti-collision module to realize the anti-collision braking control of the pipeline refueling trailer by setting multiple ultrasonic radars and photoelectric switch sensors, and controlled by the corresponding anti-collision control circuit. The overall electronic control device is safe and reliable. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of a towed aircraft refueling system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the overall structure of a towed aircraft refueling system provided in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0025] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0026] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0027] Example 1 like Figure 1 As shown, this embodiment provides a towed aircraft refueling system, including a refueling control device, an interlocking device, a hydraulic device, and an electronic control device; The refueling control device is installed on the pipeline refueling trailer and includes, in sequence, a well hose connector, a well hose, a coarse oil filter assembly, an electromagnetic pressure control valve, a rotary joint, a flow control solenoid valve, a filter, a flow meter, a safety relief valve, a reel ball valve, a venturi tube, an oil delivery hose, and a pressure refueling nozzle. The well hose connector is used to connect to the well valve on the apron to introduce aviation fuel; the pressure refueling nozzle is used to connect to the aircraft fuel tank inlet to complete refueling. Interlocking devices are used for brake interlocking and refueling circuit interlocking control of the refueling control device; The hydraulic unit is used to provide hydraulic driving force for the hydraulic actuators of the refueling trailer; The electronic control unit is used to provide control circuitry for the refueling control device.

[0028] The specific descriptions of each device are as follows.

[0029] I. Fueling Control Device 1.1 Pipeline Flow The main pipeline flow of the refueling control device is as follows: aviation fuel is introduced by connecting the well hose connector to the well valve on the apron; it passes through the well hose, coarse oil filter, PCV valve, rotary joint, and flow control solenoid valve into the filter; after passing through the flow meter, it is led to the fuel delivery hose through the safety relief valve, reel ball valve, and venturi tube. The fuel delivery hose can be a 2.5" hose, which is connected to the aircraft fuel tank inlet via a pressure refueling connector to complete the refueling.

[0030] 1.2 Aviation fuel filtration, sump draining, and venting systems The filter is equipped with a primary filter element, a secondary filter element, a filter drain pipe, a ball valve, and an automatic vent valve. The refueling control device also includes a recovery tank. Both the primary and secondary filter elements are located inside the filter. The filter drain pipe is located at the bottom of the filter. When aviation fuel passes through the filter, solid particles are filtered out by the primary filter element, and water is filtered out by the secondary filter element. The filtered water is discharged through the filter drain pipe at the bottom of the filter. The ball valve is located on top of the filter, and the automatic vent valve is connected to the ball valve. When there is gas in the pipeline of the refueling control device, the gas is discharged through the ball valve on top of the filter and the automatic vent valve. The discharged gas and the aviation fuel carried out enter the recovery tank. The safety relief valve is located on top of the filter. When the pipeline pressure of the refueling control device exceeds the pressure threshold, the aviation fuel is released through the safety relief valve into the recovery tank.

[0031] Essentially, when aviation fuel flows through the filter, solid particles are filtered out by the first-stage filter element, and water is filtered out by the second-stage filter element. The water that settles to the bottom of the filter separator is discharged through the filter drain pipe.

[0032] When there is gas in the pipeline, it will be automatically discharged through the ball valve, automatic vent valve, and observation window at the top of the filter. The discharged gas and the carried-out aviation fuel enter the recovery tank, while the gas escapes and the aviation fuel is recovered. When the pressure in the pipeline reaches 1.1 MPa (160 psi), the aviation fuel will leak through the safety valve at the top of the filter and enter the recovery tank.

[0033] 1.3. Pressure stabilization and control of aviation fuel The electromagnetic pressure control valve (PCV) is installed outside the well joint, and the opening, throttling and closing of the valve are jointly controlled by the venturi tube in the pipeline and the set pressure feedback signal in the system.

[0034] A pressure regulator is installed inside the pressure refueling nozzle to form the main pressure control. When the aircraft fuel tank is full and closed, the pressure regulator controls the valve to close, ensuring that the static pressure after the pressure refueling nozzle does not exceed 0.35MPa and the pressure fluctuation does not exceed 0.8MPa.

[0035] 1.4. Aviation fuel metering and testing devices Preferably, the filter is also connected to a self-resetting valve and a closed-circuit sampler, which is used to discharge the aviation fuel in the filter into the closed-circuit sampler, and to detect the fuel condition of the closed-circuit sampler by visual inspection or test paper. Piston-type differential pressure gauges are also connected to both the inlet and outlet ends of the filter to measure the pressure difference between the two ends of the filter.

[0036] During refueling, the measurement of aviation fuel is completed by a flow meter. The refueling truck on this pipeline is equipped with a graphite scraper flow meter.

[0037] Aviation fuel is discharged into the closed-circuit sampler through the filter outlet, the front end of the filter, and the rear end of the filter via a self-resetting valve. Solid particles and moisture in the high-speed rotating fuel can be directly visually inspected. Moisture content can also be measured by taking samples from the interface using Shell test paper or by taking samples from the micrometer wave connector.

[0038] Piston-type differential pressure gauges are used to monitor the fouling status of filter elements. When the differential pressure exceeds the specified value, the filter element should be replaced. For ease of maintenance, ball valves are installed at the sampling ports at the inlet and outlet of the filter. A self-resetting valve is also installed on the low-pressure end of the differential pressure gauge to prevent the valve core from getting stuck.

[0039] 1.5 Aviation fuel recovery, depressurization, and pipeline maintenance and pressure testing equipment Preferably, the drain port of the closed-circuit sampler and the outlet pipeline of the piston differential pressure gauge are both connected to the recovery tank for aviation fuel recovery; A 70-liter recovery tank recovers aviation fuel from the outlet of the automatic vent valve, the drain port of the closed-circuit sampler, the pressure relief valve, and the outlet pipeline of the differential pressure gauge.

[0040] Electromagnetic pressure relief valves normally release pressure in the pipeline system to 0.1–0.15 MPa. Each main pipeline ball valve has a bypass pressure relief line consisting of a check valve and a ball valve to prevent high pressure buildup caused by the thermal expansion of the fuel inside the pipeline due to sun exposure.

[0041] The control signal of the electromagnetic pressure relief valve is connected to the Daldmann control signal. When the Daldmann is operated or exceeds the Daldmann, the electromagnetic pressure relief valve cuts off the passage and maintains the pressure in the pipeline.

[0042] Each rigid tube near the hose is equipped with a test port for periodic inspection of the hose pressure test.

[0043] 1.6 Oil recovery tank pumping system Preferably, the recovered fuel tank is also connected to a fuel pumping system, which is equipped with a fuel pump. When the fuel level in the recovered fuel tank reaches a preset height threshold, the fuel pumping system is activated and the fuel pump transfers the aviation fuel in the recovered fuel tank to the front end pipe of the filter. After being filtered by the filter, the fuel is then added to the aircraft fuel tank.

[0044] In this embodiment, the differential pressure gauge self-test pressure relief pipeline, pipeline pressure relief pipeline, filter safety valve pressure relief pipeline, filter automatic venting pipeline, and closed-circuit sampler discharge pipeline are all connected to the recovery oil tank. When the kerosene level collected in the recovery oil tank reaches 75%, the oil pumping system will automatically start, passing through the oil pump, check valve, and ball valve to the front end pipeline of the filter. After filtration by the filter, the oil is then added to the aircraft fuel tank for recycling.

[0045] II. Interlocking Device 2.1 Brake Interlock Module The interlocking device includes a brake interlocking module, which is used to unlock the brake structure of the pipeline refueling trailer after all the pull-out parts on the pipeline refueling trailer have been retracted and reset; otherwise, the pipeline refueling trailer is put into a braking state by the hydraulic oil of the hydraulic device; the hydraulic drive pipeline of the brake interlocking module is connected to an emergency interlock release switch, which is used to release the braking state of the pipeline refueling trailer. Essentially, to prevent accidental operation and potential damage to aircraft or facilities due to incomplete retraction of the extended sections after refueling at the pipeline refueling unit, this pipeline refueling trailer is equipped with a hydraulic brake interlock device. This ensures that all extended sections of the pipeline trailer are retracted and properly reset before the solenoid valves reverse and the interlock is released, allowing the trailer to move away. If the interlock is not released, hydraulic oil from the hydraulic control system enters the interlock brake device, putting the trailer in a braking state.

[0046] In an emergency, operating the emergency interlock release switch will cut off the hydraulic circuit to the interlock, thus releasing the trailer brake interlock.

[0047] 2.2, Dedman Module The interlocking device also includes a Daedman module, which is communicatively connected to the electromagnetic pressure control valve and used to control the opening or closing of the oil circuit of the electromagnetic pressure control valve; the Daedman module is connected in parallel with an overriding Daedman module, which is used to control the electromagnetic pressure control valve through the overriding Daedman module when the Daedman module fails; the electromagnetic pressure control valve is also connected to a Daedman shut-off solenoid valve, which is used to cut off the control of the electromagnetic pressure control valve by the Daedman module and the overriding Daedman module.

[0048] Specifically, the Dedemann control signal is input into the PCV in the wellhead connector to open or throttle the oil passage. Releasing the Dedemann valve closes the oil passage and stops refueling.

[0049] A bypass valve is also connected in parallel with the Dydman valve. In case of a Dydman malfunction, opening the bypass valve allows for emergency refueling.

[0050] Note: The PCV control signal is also equipped with a solenoid valve to cut off the Dedman. When the liquid level in the recovery tank exceeds the set value (about 80%), or when all the interlocking points of the platform refueling connector and the reel refueling connector are reset, the PCV control opening signal will also be cut off.

[0051] 2.3 Pallet locking device Preferably, an electric push rod is installed on the well tray. When the well hose lifting mechanism is reset, the push rod is pushed out to lock the well connector. When the well hose lifting mechanism is disengaged, the push rod is retracted, so that the well connector can be removed.

[0052] III. Hydraulic Device 3.1 Hydraulic control module for well hose The hydraulic device includes a well hose hydraulic control module, which includes hydraulic outriggers, a manual directional valve, and a well hose retraction mechanism. There are multiple hydraulic outriggers. The hydraulic oil of the hydraulic device is connected to each hydraulic outrigger through the manual directional valve. Each hydraulic outrigger is connected to the well hose retraction mechanism to drive the well hose retraction mechanism to lift and lower. The well hose is installed on the well hose retraction mechanism. In this embodiment, hydraulic oil enters the four outrigger cylinders via the hydraulic outrigger lifting manual directional valve. The well hose retraction mechanism rises and falls with the hydraulic outriggers. Operating the manual directional valve automatically retracts or lowers the well hose. If the sensor at the tow bar hook fails to detect engagement, the outrigger hydraulic circuit locks, and the manual directional valve becomes ineffective.

[0053] Push the manual directional valve handle forward to retract the well hose. When the hydraulic system pressure gauge needle hovers around 11 MPa, the mechanism is in position. Release the handle to stop operation.

[0054] Pull the manual directional valve handle backward to lower the well hose. When the hydraulic system pressure gauge needle swings around 11 MPa, the mechanism is in place. Release the handle to stop operation.

[0055] When the manual reversing valve handle is in the middle position, the well hose retraction mechanism stops moving.

[0056] When the hydraulic system fails, open the return ball valves of the four cylinders and rotate the three-way ball valve handle to the vertical position. Operate the manual pump to raise the well hose reel mechanism.

[0057] 3.2 Brake Drive Module The hydraulic system also includes a brake drive module, which supplies oil to the brake circuit of the pipeline refueling trailer according to the brake signal. That is, the tractor's brake pedal provides a signal to control the electro-proportional hydraulic valve, which supplies oil to the trailer's brake oil circuit, and the amount of oil supplied controls the braking force.

[0058] The hydraulic oil used in the pipeline refueling truck is divided into normal temperature and low temperature versions. The normal temperature model uses No. 32 anti-wear hydraulic oil, and the low temperature model uses No. 20 aviation hydraulic oil. The maximum pressure of the hydraulic system is 16Mpa. The hydraulic system of this pipeline refueling trailer is powered by an independent electric hydraulic station.

[0059] IV. Electrical Control Device The electrical control system of this pipeline refueling truck operates on 24V. Its main electrical components include an on-board controller, proximity switches, push-button switches, anti-collision switches, pneumatic solenoid valves, hydraulic solenoid valves, a driving recorder, indicator lights, and lighting, primarily performing the following functions: 4.1 Interlocking Control Module The electrical control device includes an interlocking control module, which includes a controller and a controller power supply circuit. The controller is connected to an electromagnetic pressure control valve, a flow control solenoid valve, and a flow meter, respectively. The controller power supply circuit is powered by a regulated power supply. In this embodiment, the interlocking control module consists of a controller, expansion modules, solenoid valves, and indicator lights. The programmable controller is powered by a regulated power supply (24V constant voltage output). This regulated power supply is specifically designed to prevent short circuits and overloads, and has a maximum power of 180W. The circuit breaker at the input point of the regulated power supply is rated at 3A. In addition to powering the programmable controller, it also powers the three-wire proximity switches at each interlocking point. Each proximity switch input power supply is equipped with a 1A automotive circuit breaker; the circuit breaker rating should not be arbitrarily increased.

[0060] The input power to the output of the programmable controller is controlled by a key switch, which controls electrical components such as the PCV solenoid valve, hydraulic solenoid valve, interlock indicator light, and interlock reset confirmation indicator light. Each common terminal of the controller output is equipped with a circuit breaker of different specifications. The specifications of the circuit breaker must not be increased arbitrarily, otherwise an accident may occur.

[0061] The interlocking control circuit controls the following interlocking points: The system includes: wellhead connector, well hose reel mechanism, refueling ladder, reel pressure refueling nozzle, reel tank cover, wheel stop, left guide electrostatic clamp, right guide electrostatic clamp, loading arm, and refueling cantilever (refueling ladder and well hook interlocking are optional). When any of the above interlocking mechanisms leaves its original position, the indicator light at the corresponding point on the safety interlock indicator panel on the control cabinet will illuminate, and the yellow main interlock indicator light will also illuminate. After each interlocking point is reset, pressing the interlock reset confirmation button will release the brake interlock.

[0062] Note: The interlocking control system is equipped with an overrun switch. When the interlocking system fails to reset normally, opening the overrun switch will release the brakes and allow the aircraft to depart. At the same time, the corresponding red indicator light will illuminate.

[0063] 4.2 Deidmann Control Module Preferably, the electronic control device further includes a Daedman control module, which is used to control the Daedman module's circuitry. The corresponding control process includes: after the Daedman module is pressed open, the electromagnetic pressure control valve is opened and the refueling control device starts refueling; after the Daedman module is released, the electromagnetic pressure control valve is closed after a first delay; if the time for pressing open the Daedman module reaches a time threshold, a corresponding indicator light flashes to indicate this, and the electromagnetic pressure control valve is closed after the flashing reaches a first time threshold.

[0064] The specific functions implemented in this embodiment are as follows: 1. Hold the Deadman module firmly, start adding oil, release the Deadman module and delay for 0.4 seconds to shut down the PCV. This can avoid impacting the PCV when the Deadman module is reactivated. 2. Hold the Daidman module firmly and start adding oil. The indicator light on the Daidman module will light up. After working for 2.5 minutes, the indicator light on the Daidman module will start flashing at a frequency of 1 second. After flashing for 30 seconds, the PCV will be automatically cut off. 3. Hold the Daedman module firmly and start adding oil. The Daedman module indicator light will light up. After working for 2.5 minutes, the Daedman module indicator light will start to alarm. Release the Daedman module and then quickly hold it firmly to reactivate the Daedman module and make it work normally. Note: The flow meter is equipped with a self-test signal for its working status. When the flow meter malfunctions, the Dedemann programmable control system cannot be started.

[0065] 4.3 Auxiliary oil tank level control module An electronic level gauge is installed on the auxiliary oil tank. The electronic level gauge collects the changes in the liquid level of the auxiliary oil tank in real time and transmits the signal to the controller. When the liquid level reaches 75%, P1 is turned on during the refueling process, and oil pumping will start automatically until the liquid level reaches 18% or P1 is turned off to stop refueling and stop pumping. When the liquid level reaches 80%, the Dedman refueling is cut off and a high liquid level alarm is triggered at the same time.

[0066] 4.4 Anti-collision circuit for the lifting of the fuel lift bracket Preferably, the electronic control device further includes a refueling ladder bracket lifting anti-collision circuit, and the refueling control device further includes a refueling ladder bracket and a refueling ladder. The refueling ladder is installed on the refueling ladder bracket, and the refueling ladder bracket is connected to a lifting drive structure. The refueling ladder is equipped with multiple anti-collision switches. The refueling ladder bracket lifting anti-collision circuit is connected to the lifting drive structure and the anti-collision switches respectively. It is used to drive the refueling ladder bracket to rise when it receives a refueling ladder bracket lifting command; drive the refueling ladder bracket to descend when it receives a refueling ladder bracket lowering command; and trigger an alarm through the vehicle obstruction light and drive the pipeline refueling trailer to stop when it receives an anti-collision switch activation command.

[0067] In this embodiment, when the refueling elevator bracket lift button is pressed, the bracket rises; when the refueling elevator bracket lower button is pressed, the bracket lowers; during transportation, four anti-collision switches on the refueling elevator are connected in series to transmit signals to the controller input terminal. When any anti-collision switch is activated, the vehicle obstacle light on the entire device alarms, and the device automatically stops and brakes at the same time. The collision avoidance system is equipped with a dedicated overtake switch. In case of special circumstances that prevent the vehicle from driving normally, the collision avoidance overtake switch can be pressed to deactivate the collision avoidance system.

[0068] 4.5 Reel Switch Control Circuit When the reel malfunctions during winding, pressing the "Cut Reel Winding" button will cut off the winding function. The reel motor will stop working, and the reel brake will automatically engage. The reel brake is equipped with an overrun button; pressing this button will forcibly release the reel brake. When the reel brake is released, the brake indicator light will flash continuously.

[0069] 4.6 Warning light circuit, static electricity conductive motor, and vehicle display module All are controlled by the main switch for the upper equipment operation.

[0070] 4.7 Radar ranging, early warning, and collision avoidance module Preferably, the electronic control device also includes a radar ranging warning and anti-collision module, which includes multiple ultrasonic radars and photoelectric switch sensors. The ultrasonic radars and photoelectric switch sensors are respectively installed on the left and right sides of the pipeline refueling trailer. The ultrasonic radars are used to measure obstacles within the effective detection range and issue audible warnings. The photoelectric switch sensors are connected to the anti-collision system controller of the pipeline refueling trailer and are used to achieve different distance trigger signals by adjusting the photosensitive sensitivity. The radar ranging warning and collision avoidance module also includes a collision avoidance control circuit. Both the ultrasonic radar and the photoelectric switch sensor are connected to the collision avoidance control circuit. After the ultrasonic radar or the photoelectric switch sensor triggers a signal, the collision avoidance control circuit controls the interlocking device to stop the pipeline refueling trailer or drive it below the preset low speed threshold.

[0071] In this embodiment, four sets of ultrasonic radar and photoelectric switch sensors are installed around the vehicle to detect surrounding obstacles. Each set on the left and right sides of the front bumper of the driver's cab contains two ultrasonic radars and one photoelectric switch, and each set on the left and right sides of the vehicle contains one ultrasonic radar and one photoelectric switch.

[0072] The ultrasonic radar sends signals to two displays in the driver's cab to measure obstacles within 2 meters. When the vehicle approaches an object, the corresponding display will provide an audible warning and show its location. When the distance is less than 0.2 meters, the display will show "P" and a buzzer will sound continuously to signal the vehicle to stop immediately.

[0073] The photoelectric switch connects to the collision avoidance system controller, and different distance trigger signals can be achieved by adjusting the photosensitive sensitivity. When the vehicle is in first gear and traveling at a speed below 5 km / h, the radar main unit activates (with a "beep" sound) and a voice prompt "You have entered the redline area, please drive carefully" is given 3 times, lasting 10 seconds.

[0074] When one of the four photoelectric switches detects that the distance to an obstacle is less than a set value, it outputs a signal to the controller. The controller then controls the output to activate the interlocking solenoid valve, bringing the vehicle to a stop. The brakes automatically disengage after the vehicle has been stopped for 5 seconds. If the conditions for engaging first gear, driving at a speed below 5 km / h, or engaging reverse gear are not met, the collision avoidance system will automatically deactivate until the conditions are met again, at which point it will automatically reactivate.

[0075] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A towed aircraft refueling system, characterized in that, This includes refueling control devices, interlocking devices, hydraulic devices, and electrical control devices; The refueling control device is installed on the pipeline refueling trailer and includes, in sequence, a well hose connector, a well hose, a coarse oil filter assembly, an electromagnetic pressure control valve, a rotary joint, a flow control solenoid valve, a filter, a flow meter, a safety relief valve, a reel ball valve, a venturi tube, an oil delivery hose, and a pressure refueling nozzle. The well hose connector is used to connect to the well valve on the apron to introduce aviation fuel; the pressure refueling nozzle is used to connect to the aircraft fuel tank inlet to complete refueling. The interlocking device is used for brake interlocking and refueling circuit interlocking control of the refueling trailer; The hydraulic device is used to provide hydraulic driving force for the hydraulic actuators on the refueling trailer; The electronic control device is used to provide control circuitry for the refueling control device.

2. The towed aircraft refueling system according to claim 1, characterized in that, The filter is equipped with a primary filter element, a secondary filter element, a filter drain pipe, a ball valve, and an automatic venting valve. The refueling control device also includes a recovery tank. Both the primary and secondary filter elements are located inside the filter, and the filter drain pipe is located at the bottom of the filter. When aviation fuel passes through the filter, solid particles are filtered out by the primary filter element, and water is filtered out by the secondary filter element. The filtered water is discharged through the filter drain pipe at the bottom of the filter. The ball valve is located on top of the filter, and the automatic venting valve is connected to the ball valve. When there is gas in the pipeline of the refueling control device, the gas is discharged through the ball valve on top of the filter and the automatic venting valve. The discharged gas and the aviation fuel carried out enter the recovery tank. The safety relief valve is located on top of the filter. When the pipeline pressure of the refueling control device exceeds the pressure threshold, the aviation fuel is released through the safety relief valve into the recovery tank.

3. A towed aircraft refueling system according to claim 2, characterized in that, The filter is also connected to a self-resetting valve and a closed-circuit sampler, which is used to discharge aviation fuel in the filter into the closed-circuit sampler, and to detect the fuel status of the closed-circuit sampler by visual inspection or test paper. The filter is also equipped with piston-type differential pressure gauges at both the inlet and outlet ends to measure the pressure difference across the filter.

4. A towed aircraft refueling system according to claim 3, characterized in that, The oil drain port of the closed-circuit sampler and the outlet pipeline of the piston differential pressure gauge are both connected to the recovery tank for aviation fuel recovery. The recovered fuel tank is also connected to a fuel pumping system, which is equipped with a jet fuel pump. When the fuel level in the recovered fuel tank reaches a preset height threshold, the fuel pumping system is activated and the jet fuel pump transfers the aviation fuel in the recovered fuel tank to the front end pipe of the filter. After being filtered by the filter, the fuel is then added to the aircraft fuel tank.

5. A towed aircraft refueling system according to claim 1, characterized in that, The electromagnetic pressure control valve is controlled by the set pressure feedback signal measured in the venturi tube and the refueling control device. The pressure refueling nozzle is equipped with a pressure regulator. When the aircraft fuel tank is full and closed, the pressure regulator controls the electromagnetic pressure control valve to close, thereby controlling the static pressure and fluctuating pressure within the pressure refueling nozzle.

6. A towed aircraft refueling system according to claim 1, characterized in that, The interlocking device includes a brake interlocking module, which is used to unlock the brake structure of the pipeline refueling trailer after all the pull-out parts on the pipeline refueling trailer have been retracted and reset; otherwise, the pipeline refueling trailer is put into a braking state by hydraulic oil from the hydraulic device; the hydraulic drive pipeline of the brake interlocking module is connected to an emergency interlock release switch, which is used to release the braking state of the pipeline refueling trailer. The interlocking device also includes a Daedman module, which is communicatively connected to the electromagnetic pressure control valve and used to control the opening or closing of the oil circuit of the electromagnetic pressure control valve; the Daedman module is connected in parallel with an overriding Daedman module, which is used to control the electromagnetic pressure control valve through the overriding Daedman module when the Daedman module fails; the electromagnetic pressure control valve is also connected to a Daedman shut-off solenoid valve, which is used to cut off the control of the electromagnetic pressure control valve by the Daedman module and the overriding Daedman module.

7. A towed aircraft refueling system according to claim 1, characterized in that, The hydraulic device includes a well hose hydraulic control module, which includes hydraulic outriggers, a manual directional valve, and a well hose retraction mechanism. There are multiple hydraulic outriggers. The hydraulic oil of the hydraulic device is connected to each hydraulic outrigger through the manual directional valve. Each hydraulic outrigger is connected to the well hose retraction mechanism to drive the well hose retraction mechanism to lift and lower. The well hose is installed on the well hose retraction mechanism. The hydraulic device also includes a brake drive module, which is used to supply oil to the brake structure oil circuit of the pipeline refueling trailer according to the brake signal. The hydraulic oil for the hydraulic device is supplied by an electro-hydraulic power unit.

8. A towed aircraft refueling system according to claim 6, characterized in that, The electronic control device includes an interlocking control module, which includes a controller and a controller power supply circuit. The controller is connected to an electromagnetic pressure control valve, a flow control solenoid valve, and a flow meter, respectively. The controller power supply circuit is powered by a regulated power supply. The electronic control device also includes a Daedman control module, which is used to control the Daedman module's circuitry. The corresponding control process includes: after the Daedman module is pressed open, the electromagnetic pressure control valve is opened and the refueling control device starts refueling; after the Daedman module is released, the electromagnetic pressure control valve is closed after a first delay; if the time for pressing open the Daedman module reaches a time threshold, a corresponding indicator light will flash to indicate this, and the electromagnetic pressure control valve will be closed after the flashing reaches a first time.

9. A towed aircraft refueling system according to claim 1, characterized in that, The electronic control device also includes a refueling ladder bracket lifting anti-collision circuit. The refueling control device also includes a refueling ladder bracket and a refueling ladder. The refueling ladder is installed on the refueling ladder bracket, and the refueling ladder bracket is connected to a lifting drive structure. The refueling ladder is equipped with multiple anti-collision switches. The refueling ladder bracket lifting anti-collision circuit is connected to the lifting drive structure and the anti-collision switches respectively. It is used to drive the refueling ladder bracket to rise when it receives a refueling ladder bracket lifting command; drive the refueling ladder bracket to descend when it receives a refueling ladder bracket lowering command; and trigger an alarm through the vehicle obstruction light and drive the pipeline refueling trailer to stop when it receives an anti-collision switch activation command.

10. A towed aircraft refueling system according to claim 1, characterized in that, The electronic control device also includes a radar ranging and early warning collision avoidance module, which includes multiple ultrasonic radars and photoelectric switch sensors. The ultrasonic radars and photoelectric switch sensors are respectively installed on the left and right sides of the pipeline refueling trailer. The ultrasonic radars are used to measure obstacles within the effective detection range and issue audible alerts. The photoelectric switch sensors are connected to the collision avoidance system controller of the pipeline refueling trailer and are used to achieve different distance trigger signals by adjusting the photosensitivity. The radar ranging warning and collision avoidance module also includes a collision avoidance control circuit. The ultrasonic radar and photoelectric switch sensor are both connected to the collision avoidance control circuit. After the ultrasonic radar or photoelectric switch sensor triggers a signal, the collision avoidance control circuit controls the interlocking device to drive the pipeline refueling trailer to a stop or to drive below a preset low speed threshold.

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