A safety control refueling system and safety control method thereof

Abstract

The present invention relates to a safety control refueling system, belonging to the technical field of pressure refueling. The system includes a main pipeline from the oil tank outlet to the refueling gun via an oil pump, a filter separator, a pressure control valve, and a venturi tube; a first pressure transmitter is installed between the filter separator and the pressure control valve, and the oil pump is connected in parallel to protect the branch; a pressure relief branch is branched between the filter separator and the pressure control valve; an automatic exhaust valve is installed on the upper part of the filter separator, and a fuel water sensor is installed in the filter separator; the signal output ends of the speed sensor, the first pressure transmitter, the second pressure transmitter, the proximity switch, and the fuel water sensor are connected to the controlled ends of the electromagnetic overflow valve, the air control valve, and the pressure control valve through a PLC controller. The use of the present invention can effectively avoid the impact vibration caused by factors such as excessive pressure, reliably protect the filter separator filter element and the precision components of the pipeline system, and effectively ensure the safety and reliability of pressure refueling operations.

Description

Technical Field

[0001] The invention relates to a refueling system, in particular to a safety-controlled refueling system, and also to a corresponding safety control method, belonging to the technical field of pressure refueling. Background Art

[0002] Pressure refueling is widely used in aviation equipment such as helicopters, fixed-wing aircraft, and drones. These equipment have high requirements on the quality of the refueling oil and the stability of refueling.

[0003] Studies have shown that tiny particles in oil products carry static electricity and water molecules have polarity, which will form charged hydrated particles. Under the electrostatic adsorption of low-temperature environments, hydrated particles can easily condense into particle clusters and mix in the oil flow, gathering in the dead zone of the pipeline system, posing a safety hazard. Therefore, the pressure refueling pipeline system needs to be equipped with a filter separator, using coalescing filter elements and separation filter elements to filter out solid particles, fibers and moisture in the oil to ensure the quality of the oil products; at the same time, the residual air in the filter separator is emptied through the automatic exhaust valve to avoid air in the pipeline from impacting the filter element and causing damage to the filter element during high-flow refueling operations.

[0004] According to the applicant, the existing maintenance method for the filter separator is to detect the quality of the fuel after filtration and the differential pressure of the filter separator to determine whether to clean or replace the filter element, or to replace it regularly. However, during the system refueling operation, it is only possible to determine whether the filter separator is normal by observing the differential pressure gauge, which makes it difficult to achieve quantitative detection and real-time control. In addition, it is impossible to determine whether there is residual air in the filter separator. Often when it is discovered, the refueling pipeline system has already experienced impact vibration. This situation not only leads to a decrease in the performance and service life of the refueling system, but also poses a safety hazard. Summary of the invention

[0005] The purpose of the present invention is to provide a safe control refueling system that can realize real-time detection and control of the working conditions of the filter separator in order to solve the problems existing in the above-mentioned prior art, thereby avoiding impact vibration caused by excessive gas or pressure, and improving the safety and reliability of the pressure refueling operation process.

[0006] In order to achieve the above objectives, the basic technical scheme of the safety control refueling system of the present invention is as follows: it includes a main pipeline from the oil tank outlet through an oil pump with a speed sensor, a filter separator, a pressure control valve, and a venturi tube to the refueling gun;

[0007] A first pressure transmitter is installed between the filter separator and the pressure control valve, and the oil pump is connected in parallel with a protection branch containing an air control valve and a second pressure transmitter;

[0008] A pressure relief branch is branched between the filter separator and the pressure control valve and returns to the front end of the oil pump through the electromagnetic overflow valve;

[0009] An automatic exhaust valve with a proximity switch is installed on the upper part of the filter separator, and a fuel moisture sensor is installed in the filter separator;

[0010] The feedback signal end of the venturi tube is connected to the feedback control end of the pressure control valve;

[0011] The signal output ends of the speed sensor, the first pressure transmitter, the second pressure transmitter, the proximity switch, and the fuel moisture sensor are respectively connected to the corresponding signal input ends of the PLC controller, and the control signal output ends of the PLC controller are respectively connected to the controlled end of the electromagnetic overflow valve, and the controlled end of the air-controlled switching valve in the corresponding air-controlled pipelines of the air-controlled valve and the pressure control valve.

[0012] After startup, the PLC controller implements refueling safety control according to the following logic:

[0013] Step 1, exhaust control - judge whether the exhaust is completed according to the proximity switch signal. If not, control the air control valve to close, the pressure control valve to close, the automatic exhaust valve to continue exhausting, and judge again whether the exhaust is completed; if yes, proceed to the next step;

[0014] Step 2, refueling control - determine whether the fuel water sensor signal is lower than the water threshold, the first pressure transmitter and the second pressure transmitter signal are respectively lower than the corresponding pressure thresholds. If so, control the pressure control valve to open, the air control valve to close, and the electromagnetic overflow valve to close, gradually increase the pump speed to perform pressure refueling operations, and proceed to the next step after a predetermined time interval; otherwise, proceed to step 4;

[0015] Step 3: Pressure differential protection - determine whether the pressure differential between the first pressure transmitter and the second pressure transmitter is greater than a predetermined value, if not, return to step 2; if yes, issue an alarm and proceed to step 7;

[0016] Step 4: Overpressure protection - determine whether the signal of the second pressure transmitter exceeds the corresponding threshold. If so, control the electromagnetic overflow valve to open and the air control valve to open, and return to step 2; otherwise, proceed to the next step;

[0017] Step 5, overpressure protection - determine whether the signal of the first pressure transmitter exceeds the corresponding threshold value. If so, control the electromagnetic overflow valve to open and the air control valve to open, and proceed to step 7; otherwise, proceed to the next step;

[0018] Step 6: Over-humidity protection: When judging whether the fuel moisture sensor signal exceeds the water content threshold, if so, the pressure control valve is quickly closed, the electromagnetic overflow valve is opened, and the air control valve is opened, and the seventh step is performed; otherwise, return to the second step;

[0019] Step 7: Shutdown.

[0020] It can be seen that after adopting the present invention, the entire pressure refueling pipeline system can be monitored in real time, effectively avoiding impact vibration caused by factors such as excessive pressure, reliably protecting the filter separator element and precision components of the pipeline system, and effectively ensuring the safety and reliability of pressure refueling operations.

[0021] A further improvement of the present invention is that the can-shaped valve body of the automatic exhaust valve is covered with a valve cover with an exhaust port and an air outlet, a float is arranged in the valve body, the upper part of the float is connected to a vertical valve stem, the lower end of the valve stem has an inverted cone-shaped valve disc, and a proximity switch is installed on the top of the valve cover opposite to the upper end of the valve stem.

[0022] A further improvement of the present invention is that: the air source of the air control pipeline is connected to the first inlet port of the two-position five-way solenoid valve through a two-position three-way solenoid valve, and is connected to the third inlet port of the two-position five-way solenoid valve in another way; the second inlet port of the two-position five-way solenoid valve is connected to the quick exhaust valve; the pressure control valve is a double-control pressure control valve controlled by a feedback control end and an air pressure control end, the first outlet port of the two-position five-way solenoid valve is connected to the air pressure control end of the pressure control valve, and the second outlet port thereof is connected to the idle cylinder control end of the throttle controller of the oil pump drive motor.

[0023] A further improvement of the present invention is that an idle cylinder is placed at one end of the base plate of the throttle controller, the telescopic end of the idle cylinder is fixedly connected to one end of a horizontal rack, the other end of the horizontal rack is connected to a throttle control rope, and a throttle wrench is hinged on the base plate, and the hinged end of the throttle wrench is fixedly connected to a fan-shaped gear meshing with the horizontal rack. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The figure is a schematic diagram of the structure of a pipeline system according to an embodiment of the present invention.

[0025] Figure 2 for Figure 1 Schematic diagram of the automatic exhaust valve structure of an embodiment.

[0026] Figure 3 for Figure 1 Schematic diagram of the throttle controller structure of an embodiment.

[0027] Figure 4 for Figure 1 A control logic block diagram of an embodiment. DETAILED DESCRIPTION Example

[0028] The safety control refueling system of this embodiment is installed in the apron. Figure 1As shown, the oil tank outlet passes through the oil pump P with a speed sensor 302, the filter separator F for filtering moisture and impurities in light fuel, the pressure control valve 201, the pressure gauge, the venturi 202, and the refueling coil J to the refueling gun G, as shown in the double-line main line. A first pressure transmitter 303 is installed between the filter separator F and the pressure control valve 201, and the oil pump P is connected in parallel with a protection branch containing an air control valve 204 and a second pressure transmitter 304. A pressure relief branch is branched between the filter separator F and the pressure control valve 201, which returns to the front end of the oil pump P through the electromagnetic overflow valve 203.

[0029] The pressure control valve 201 is a dual-control pressure control valve controlled by a feedback control end and an air pressure control end. The feedback signal end of the venturi tube 202 is connected to its feedback control end. When an abnormal signal is fed back, the pressure control valve can be forcibly closed.

[0030] The gas source Q of the gas control pipeline of this embodiment is divided into two paths after passing through the gas source processing triplet S. One path is connected to the first inlet of the two-position three-way solenoid valve 306 through the two-position three-way solenoid valve 301, and the other path is connected to the third inlet of the two-position five-way solenoid valve 306. The second inlet of the two-position five-way solenoid valve 306 is connected to the quick exhaust valve 307. The first outlet of the two-position five-way solenoid valve 306 is connected to the air pressure control end of the pressure control valve 201; and the second outlet of the two-position five-way solenoid valve 306 is connected to the idle cylinder control end of the throttle controller Y of the fuel motor driven by the oil pump after passing through the throttle valve 205. The specific structure of the throttle controller Y is as follows Figure 3 As shown, an idle cylinder Y-2 is placed at one end of the base plate Y-1, and the telescopic end of the idle cylinder Y-2 is fixedly connected to one end of the horizontal rack Y-6, and the other end of the horizontal rack Y-6 is connected to the throttle control rope Y-5. A throttle wrench Y-3 is also hinged on the base plate Y-1, and the hinged end of the throttle wrench Y-3 is fixedly connected to the fan-shaped gear Y-4 meshing with the horizontal rack Y-6. The throttle wrench can be used to adjust the throttle size of the fuel motor driven by the oil pump, thereby adjusting the speed of the fuel pump; and when the idle cylinder is ventilated, the throttle will be forced to be in the idle state of the fuel motor driven by the oil pump.

[0031] The filter separator F contains a sedimentation tank and a coalescing filter element, and a fuel water sensor 104 is installed between the sedimentation tank and the coalescing filter element. The filter separator F of this embodiment is equipped with a homemade automatic exhaust valve V with a proximity switch 103 on the upper part, and its specific structure is as follows: Figure 2As shown, the can-shaped valve body V-1 is covered with a valve cover V-3 with an exhaust port V-4 and an air outlet V-6, and a float V-2 is placed in the valve body 1. The upper part of the float V-2 is connected to the vertical valve stem V-5, and the lower end of the valve stem V-5 has an inverted cone valve disc V-7 that can block the air outlet V-6. A proximity switch opposite to the upper end of the valve stem V-5 is installed on the top of the valve cover V-3. When the float rises and the valve disc blocks the air outlet, the exhaust ends, and the upper end of the valve stem is close to the proximity switch to make it send a signal. The automatic exhaust valve can be purchased on demand. Therefore, the proximity switch signal determined by the up and down displacement of the valve stem above the float can be used to determine whether the filter separator has completed exhaust.

[0032] The signal output ends of the speed sensor 302, the first pressure transmitter 303, the second pressure transmitter 304, the proximity switch 103, and the fuel moisture sensor 104 are respectively connected to the corresponding signal input ends of the PLC controller, and the control signal output ends of the PLC controller are respectively connected to the controlled end of the electromagnetic overflow valve 203, and the controlled ends of the two-position three-way electromagnetic valve 301 and the two-position five-way electromagnetic valve 306 which are the air-controlled switching valves in the corresponding air-controlled pipelines of the air-controlled valve 204 and the pressure control valve 201, and their warning output ends are connected to the indicator light L.

[0033] The models and manufacturers of the main purchased parts in this embodiment are as follows:

[0034]

[0035] The safety control refueling system of this embodiment has the following operating states under the control of the PLC controller:

[0036] 1. Filter separator (101) exhaust

[0037] Connect the pressure refueling gun to the aircraft fuel tank, start the oil pump, the speed sensor is in low speed state, the two-position three-way solenoid valve is powered off, the two-position five-way solenoid valve is powered off, the air control valve is closed, the pressure control valve is closed, and the automatic exhaust valve is exhausted.

[0038] 2. Pressure refueling operation:

[0039] When the automatic exhaust valve finishes exhausting, the float rises and drives the valve stem, the proximity switch closes, the second pressure transmitter at the oil pump outlet does not exceed the rated pressure of the oil pump, and the value of the fuel moisture sensor in the filter separator does not exceed the standard, the two-position three-way solenoid valve is energized, the two-position five-way solenoid valve is de-energized, the indicator light is green, the Venturi tube feedback pressure is normal, the pressure control valve is opened, the throttle controller is used to increase the pump speed, and the pipeline system performs pressure refueling operations.

[0040] 3. Pipeline pressure safety protection:

[0041] (1) Overpressure protection

[0042] The value of the second pressure transmitter at the outlet of the oil pump exceeds the rated pressure of the oil pump, and the two-position five-way solenoid valve is energized and the indicator light turns red; the quick exhaust valve exhausts air, and the pressure control valve closes quickly; the electromagnetic overflow valve is energized, and the main pipeline is depressurized; the air control valve opens, and the idle cylinder of the throttle controller controls the throttle to return to idle speed through the rack mechanism, and the pump circulates outside to avoid continuous increase in pipeline system pressure. When the value of the second pressure transmitter at the outlet of the oil pump drops below the set value (usually less than the rated pressure) and the speed sensor value drops to idle speed for two minutes, the oil pump self-circulates normally, the two-position five-way solenoid valve is controlled to be de-energized, and the pressure refueling operation continues.

[0043] (2) Overvoltage protection

[0044] Once the feedback pressure of the venturi exceeds the standard or the air supply line of the pressure control valve is disconnected, making the value of the first pressure transmitter exceed 1.2 times the rated pressure of the pipeline system, the pressure control valve is controlled to close urgently and the indicator light turns red to warn; the electromagnetic relief valve is controlled to be energized to release the pressure in the main line; the air control valve is opened to circulate the pump externally; and the cylinder in the throttle controller is controlled to return the throttle to idle speed through the rack mechanism to avoid impact on the pipeline.

[0045] (3) Ultra-humidity protection

[0046] Once the value of the fuel moisture sensor exceeds the standard, the two-position five-way solenoid valve is always energized and the indicator light turns red for warning; the quick exhaust valve exhausts air and the pressure control valve closes quickly; the solenoid overflow valve is energized and opened to release the pressure in the main line; the air control valve opens and the pump circulates externally; and the cylinder in the throttle controller controls the throttle to return to idle speed through the rack mechanism to avoid impact on the pipeline.

[0047] (4) Pressure difference protection

[0048] When the difference between the value of the second pressure transmitter reflecting the differential pressure of the filter separator and the value of the first pressure transmitter exceeds the allowable value, the control indicator light turns red to warn, the filter separator is abnormal, and shuts down.

[0049] 4. End of downtime

[0050] The pump speed drops to 0, the two-position three-way solenoid valve, the two-position five-way solenoid valve and the solenoid overflow valve are powered off, the indicator light goes out, the air control valve is closed, the pressure control valve is closed, and the refueling operation is completed.

[0051] Note: The above two-position five-way solenoid valve is always energized; the two-position five-way solenoid valve will only be de-energized when the pump speed is 0 and the operation is completed.

[0052] The control logic of the PLC controller can be found in Figure 4 , the main steps are:

[0053] Step 1, exhaust control - judge whether the exhaust is completed according to the proximity switch signal. If not, the air control valve and pressure control valve are closed by controlling the two-position three-way solenoid valve and the two-position five-way solenoid valve to cut off the power, and the automatic exhaust valve continues to exhaust. And judge whether the exhaust is completed again; if yes, proceed to the next step;

[0054] Step 2, refueling control - determine whether the fuel moisture sensor signal is lower than the moisture threshold, the first pressure transmitter and the second pressure transmitter signal are respectively lower than the corresponding pressure thresholds. If so, control the two-position three-way solenoid valve to be energized, the two-position five-way solenoid valve to be de-energized, so that the pressure control valve is opened, the air control valve is closed, and the electromagnetic overflow valve is closed, and the pump speed is gradually increased through the throttle controller to perform pressure refueling operations, and the next step is performed after a predetermined time interval; otherwise, proceed to step 4;

[0055] Step 3: Pressure differential protection - determine whether the pressure differential between the first pressure transmitter and the second pressure transmitter is greater than a predetermined value, if not, return to step 2; if yes, issue an alarm and proceed to step 7;

[0056] Step 4: Overpressure protection - determine whether the signal of the second pressure transmitter exceeds the corresponding threshold. If so, control the electromagnetic relief valve to open, release the main pipeline pressure, control the air control valve to open, pump external circulation, and control the idle cylinder to make the throttle idle to avoid continuous increase in pipeline system pressure, and return to step 2; if not, proceed to the next step;

[0057] Step 5, overpressure protection - determine whether the signal of the first pressure transmitter exceeds the corresponding threshold value. If so, control the electromagnetic overflow valve to open, release the pressure of the main pipeline, control the air control valve to open, pump external circulation, and control the idle cylinder to make the throttle idle to avoid continuous increase of pipeline system pressure, and proceed to step 7; otherwise, proceed to the next step;

[0058] Step 6: Over-humidity protection: When judging whether the fuel moisture sensor signal exceeds the water content threshold, if so, the pressure control valve is quickly closed, the electromagnetic overflow valve is opened, and the air control valve is opened, and the seventh step is performed; otherwise, return to the second step;

[0059] Step 7: Shutdown.

[0060] Tests show that this embodiment is applicable to various pressure refueling pipeline systems containing filter separators, and can significantly improve the safety and reliability of refueling operations. In addition to the above embodiments, the present invention can also have other implementations. For example, an electronically controlled throttle controller is used, and an air-controlled valve is replaced by an electronically controlled valve. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A safety control method for a safety control refueling system, the refueling system comprising a main pipeline from the oil tank outlet to the refueling gun via an oil pump with a speed sensor, a filter separator, a pressure control valve, and a venturi; A first pressure transmitter is installed between the filter separator and the pressure control valve, and the oil pump is connected in parallel with a protection branch containing an air control valve and a second pressure transmitter; A pressure relief branch is branched between the filter separator and the pressure control valve and returns to the front end of the oil pump through the electromagnetic overflow valve; An automatic exhaust valve with a proximity switch is installed on the upper part of the filter separator, and a fuel moisture sensor is installed in the filter separator; The feedback signal end of the venturi tube is connected to the feedback control end of the pressure control valve; The signal output ends of the speed sensor, the first pressure transmitter, the second pressure transmitter, the proximity switch, and the fuel moisture sensor are respectively connected to the corresponding signal input ends of the PLC controller, and the control signal output ends of the PLC controller are respectively connected to the controlled end of the electromagnetic overflow valve, and the controlled end of the air-controlled switching valve in the corresponding air-controlled pipelines of the air-controlled valve and the pressure control valve; Features After startup, the safety control steps of the PLC controller are: Step 1, exhaust control - judge whether the exhaust is completed according to the proximity switch signal. If not, control the air control valve to close, the pressure control valve to close, the automatic exhaust valve to continue exhausting, and judge again whether the exhaust is completed; if yes, proceed to the next step; Step 2, refueling control - determine whether the fuel water sensor signal is lower than the water threshold, the first pressure transmitter and the second pressure transmitter signal are respectively lower than the corresponding pressure thresholds. If so, control the pressure control valve to open, the air control valve to close, and the electromagnetic overflow valve to close, gradually increase the pump speed to perform pressure refueling, and proceed to the next step after a predetermined time interval; otherwise, proceed to step 4; Step 3: Pressure differential protection - determine whether the pressure differential between the first pressure transmitter and the second pressure transmitter is greater than a predetermined value, if not, return to step 2; if yes, issue an alarm and proceed to step 7; Step 4: Overpressure protection - determine whether the signal of the second pressure transmitter exceeds the corresponding threshold. If so, control the electromagnetic overflow valve to open and the air control valve to open, and return to step 2; otherwise, proceed to the next step; Step 5, overpressure protection - determine whether the signal of the first pressure transmitter exceeds the corresponding threshold value. If so, control the electromagnetic overflow valve to open and the air control valve to open, and proceed to step 7; otherwise, proceed to the next step; Step 6: Over-humidity protection: When judging whether the fuel moisture sensor signal exceeds the water content threshold, if so, the pressure control valve is quickly closed, the electromagnetic overflow valve is opened, and the air control valve is opened, and the seventh step is performed; otherwise, return to the second step; Step 7: Shutdown.

2. The safety control method for a safety control refueling system according to claim 1, characterized in that: The can-shaped valve body of the automatic exhaust valve is covered with a valve cover with an exhaust port and an air outlet, a float is arranged in the valve body, the upper part of the float is connected to a vertical valve stem, the lower end of the valve stem has an inverted cone-shaped valve flap, and a proximity switch opposite to the upper end of the valve stem is installed on the top of the valve cover.

3. The safety control method for a safety control refueling system according to claim 2, characterized in that: The air source of the air control pipeline is connected to the first inlet of the two-position five-way solenoid valve through a two-position three-way solenoid valve on one way and to the third inlet of the two-position five-way solenoid valve on the other way. The second inlet of the two-position five-way solenoid valve is connected to a quick exhaust valve; the pressure control valve is a double-control pressure control valve controlled by a feedback control end and an air pressure control end. The first outlet of the two-position five-way solenoid valve is connected to the air pressure control end of the pressure control valve, and the second outlet of the two-position five-way solenoid valve is connected to the idle cylinder control end of the throttle controller of the oil pump drive motor.

4. The safety control method for a safety control refueling system according to claim 3, characterized in that: An idle cylinder is placed at one end of the base plate of the throttle controller, the telescopic end of the idle cylinder is fixedly connected to one end of a horizontal rack, the other end of the horizontal rack is connected to a throttle control rope, and a throttle wrench is also hinged on the base plate, and the hinged end of the throttle wrench is fixedly connected to a fan-shaped gear meshing with the horizontal rack.

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