Low-pressure shutdown and rapid start device for diesel engine of Dongfeng 5 diesel locomotive

Abstract

The present application relates to the technical field of electric control of internal combustion engine, in particular to a low-pressure shutdown and rapid start device for the lubricating oil of a diesel engine of a Dongfeng 5 type internal combustion engine vehicle, which comprises a fuel pump switch 4K, an intermediate relay 4ZJ and a fuel pump contactor RBC, one end of the fuel pump switch 4K is connected to the positive pole of a power supply, the other end is connected to the intermediate relay 4ZJ, the other end of the intermediate relay 4ZJ is connected in parallel with the negative pole of the power supply, and a first branch, a second branch, a third branch and a fourth branch are connected in parallel between the other end of the intermediate relay 4ZJ and the negative pole of the power supply; the fuel pump contactor RBC is connected in series on the first branch. The device provided by the present application can rapidly restart the diesel engine automatically without manual intervention when the diesel engine is still in high-speed coasting after the diesel engine is shut down due to instantaneous low lubricating oil pressure, and can shorten the running time of the vehicle without traction power and air brake power to the shortest, and can greatly reduce the safety risk of the vehicle without traction power and air brake power.

Description

Technical Field

[0001] This invention relates to the field of electrical control technology for diesel locomotives, specifically a rapid start-up device for the diesel engine of the Dongfeng 5 diesel locomotive after a low-pressure shutdown due to low lubricating oil. Background Technology

[0002] Diesel locomotives use diesel engines as their power source. The continuous traction power required for train operation and the continuous air pressure required for train braking are all output by the diesel engine.

[0003] The diesel engine requires the LDT (Low Discharge Transmission) electromagnet to engage before supplying fuel to the injection pump. The injection pump atomizes the fuel and injects it into the cylinder. Under the reciprocating compression motion of the piston in the cylinder, the space inside the cylinder becomes smaller and the temperature rises. The atomized fuel explodes, and its volume increases instantaneously. This drives the crankshaft to rotate through the piston, and the diesel engine begins to operate normally.

[0004] To ensure the normal operation of all moving parts of the diesel engine, lubricating oil is required to lubricate them. An oil pressure relay (1YJ) is installed after the oil filter line of the turbocharger, located at the highest point of the diesel engine, to monitor the lubricating oil pressure during engine operation. Long-term verification has shown that when this oil pressure drops below 80 kPa, the turbocharger may experience rotor seizure due to prolonged high-speed operation, leading to serious accidents such as engine shutdown. After the diesel engine starts running, the main oil pump, which rotates with the crankshaft, begins pumping oil to continuously supply lubricating oil pressure to the engine.

[0005] Therefore, in the circuit design of the Dongfeng 5 diesel locomotive, the normally open contact of the 1YJ oil pressure relay is connected in series with the LDT coil of the interlocking electromagnet. When the diesel engine is running, if the 1YJ oil pressure is lower than 80 kPa, the LDT interlocking electromagnet is de-energized, cutting off the fuel supply to the diesel engine, stopping the engine, and protecting the moving parts of the diesel engine from damage.

[0006] In practical applications, due to the constant movement of the crankshaft and pistons in the diesel engine, and the continuous flow of engine oil, the pressure may at a certain moment during engine operation fall slightly below 80 kPa. This causes the oil pressure relay 1YJ to disconnect, de-energizing the interlocking solenoid and cutting off the fuel supply to the diesel engine, thus stopping it. According to the circuit design of the Dongfeng 5 diesel locomotive, this shutdown occurs without any fault indication, and the driver must rely on experience to determine the cause.

[0007] An investigation revealed that there were cases across all railway bureaus nationwide where Dongfeng 5 diesel locomotives experienced sudden diesel engine shutdowns without the locomotive reporting a fault. Upon returning to the depot, the locomotives were found to be functioning normally. This type of malfunction disrupted the normal transport operations of railway locomotives.

[0008] After the diesel engine stops, in order to ensure the locomotive continues to run, the driver must restore the traction condition to the condition before starting. Following the operating sequence of the stationary state, disconnect the engine control switch 2K, return the driver's controller handle to the zero position, and press the start button for 45 seconds to restart the diesel engine.

[0009] Based on a locomotive operating speed of 100 km / h, within those 45 seconds, the locomotive would slide for 100 × 1000 m / 3600 seconds × 45 seconds = 1250 meters without traction power or air braking, with unimaginable safety consequences.

[0010] Therefore, how to ensure that the diesel engine can be quickly and automatically restarted while it is still coasting at high speed after a sudden drop in oil pressure, thus minimizing the time the locomotive is without traction power and air braking force, has become an urgent problem to be solved. Summary of the Invention

[0011] In response to the problems pointed out in the background art, the purpose of this invention is to provide a rapid start device for the diesel engine of Dongfeng 5 diesel locomotive after a low-pressure shutdown due to low oil pressure. After a shutdown caused by a momentary low oil pressure, the device can immediately and automatically start the diesel engine while it is still coasting at high speed, thus shortening the time the locomotive is in operation without traction power and without air braking force.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] The Dongfeng 5 diesel locomotive diesel engine has a rapid start device after low-pressure shutdown of lubricating oil, which includes a fuel pump switch 4K, an intermediate relay 4ZJ, and a fuel pump contactor RBC. One end of the fuel pump switch 4K is connected to the positive terminal of the power supply, and the other end is connected to the normally closed contact of the intermediate relay 4ZJ. The other end of the normally closed contact of the intermediate relay 4ZJ is connected in parallel with the negative terminal of the power supply through a first branch, a second branch, a third branch, and a fourth branch. The fuel pump contactor RBC is connected in series in the first branch.

[0014] The second branch includes a parallel switch circuit, an interlocking electromagnet LDT, a third normally open switch, and a step-down resistor Rldt. One end of the parallel switch circuit is connected to an intermediate relay 4ZJ, and the other end is connected to the input terminal of the interlocking electromagnet LDT. The input terminal of the third normally open switch is connected to the intermediate relay 4ZJ, and the output terminal is connected to the step-down resistor Rldt. The other end of the step-down resistor Rldt is connected to the input terminal of the interlocking electromagnet LDT. The output terminal of the interlocking electromagnet LDT is connected to the negative terminal of the power supply. The interlocking electromagnet LDT controls the on / off of the fuel supply line of the Dongfeng 5 diesel locomotive's diesel engine. The third normally open switch is the normally open contact of an oil pressure relay 1YJ. The oil pressure relay 1YJ is installed in the pipeline after the oil filter of the turbocharger at the highest position of the Dongfeng 5 diesel locomotive's diesel engine. When the pressure is below 80 kPa, the third normally open switch is open; when the pressure is above 100 kPa, the third normally open switch is closed. The parallel circuit includes a first normally open switch and a second normally open switch, which are connected in parallel.

[0015] The output terminal of the third normally open switch is connected to a fifth branch, which includes a first normally closed switch and an anti-stop relay FTJ1. The input terminal of the first normally closed switch is connected to the output terminal of the third normally open switch, and the output terminal of the first normally closed switch is connected to the anti-stop relay FTJ1. The other end of the anti-stop relay FTJ1 is connected to the negative terminal of the power supply.

[0016] The third branch includes a second normally closed switch, a third normally closed switch and a time relay SJ3. The input terminal of the second normally closed switch is connected to the intermediate relay 4ZJ, and the output terminal is connected to the positive terminals of the working power supplies of the third normally closed switch and the time relay SJ3 respectively. The other end of the third normally closed switch is connected to the positive terminal of the starting power supply of the time relay SJ3, and the positive terminal of the working power supply of the time relay SJ3 is connected to the negative terminal of the power supply.

[0017] The fourth branch includes a fourth normally closed switch, an anti-shutdown relay FTJ2, and a power-on delay switch connected in series. The power-on delay switch is the normally open contact of a time relay SJ3, and the power-on delay time of the power-on delay switch is less than or equal to 10 seconds.

[0018] The second normally open switch, the first normally closed switch, and the second normally closed switch are all controlled by the starting contactor QC. The second normally open switch is the auxiliary normally open contact of the starting contactor QC, the first normally closed switch is the first normally closed contact of the starting contactor QC, and the second normally closed switch is the second normally closed contact of the starting contactor QC. The starting contactor QC is controlled by the locomotive start button. After the locomotive start button is pressed for 45 seconds, the main normally open contact of the starting contactor QC closes, driving the starter generator to rotate. At the same time, the first and second normally closed contacts of the starting contactor QC change from closed to open, and the auxiliary normally open contact changes from open to closed.

[0019] The first normally open switch is the first normally open contact of the anti-shutdown relay FTJ2.

[0020] The third normally closed switch is the first normally closed contact of the anti-stop relay FTJ1, and the fourth normally closed switch is the second normally closed contact of the anti-stop relay FTJ1.

[0021] The fifth branch also includes a fourth normally open switch and an audible and visual alarm BJ connected in series. One end of the fourth normally open switch is connected to the output terminal of the first normally closed switch, and the other end is connected to the audible and visual alarm BJ. The other end of the audible and visual alarm BJ is connected to the negative terminal of the power supply. The fourth normally open switch is the second normally open contact of the anti-stop relay FTJ2.

[0022] The power-on delay time of the power-on delay switch is equal to 10 seconds.

[0023] The beneficial effects of the present invention are as follows: The device provided by the present invention can quickly and automatically restart the diesel engine after it stops due to a sudden drop in oil pressure, while the diesel engine is still coasting at high speed, without manual intervention. This minimizes the time that the locomotive is in operation without traction power and air braking force, and reduces the safety risks of the locomotive being in operation without traction power and air braking force to the greatest extent. Attached Figure Description

[0024] Figure 1 This is the circuit diagram of the present invention.

[0025] Figure 2 This is a schematic diagram showing the operational status of each component in the device within 45 seconds of pressing the start button.

[0026] Figure 3 This diagram illustrates the operational status of various components within the device from the moment the contactor QC is activated until the oil pressure of the hydraulic relay 1YJ exceeds 80 kPa.

[0027] Figure 4 This diagram illustrates the operational status of various components within the device when the oil pressure of the hydraulic relay 1YJ exceeds 80 kPa after the start button is released and the start contactor QC is released, and the diesel engine is running normally.

[0028] Figure 5 This is a schematic diagram showing the operational status of various components within the device within 10 seconds after the oil pressure of the 1YJ hydraulic relay drops below 80 kPa.

[0029] Figure 6 This diagram illustrates the operational status of various components within the device when the oil pressure of the oil pressure relay 1YJ exceeds 80 kPa after the diesel engine restarts. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0031] This invention provides a rapid start device for a Dongfeng 5 diesel locomotive diesel engine after a low-pressure shutdown of the lubricating oil, comprising a fuel pump switch 4K, an intermediate relay 4ZJ, a starting contactor QC, a fuel pump contactor RBC, an interlocking electromagnet LDT, a fuel injection pump, a voltage-reducing resistor Rldt, an oil pressure relay 1YJ, an anti-shutdown relay FTJ1, an anti-shutdown relay FTJ2, a time relay SJ3, and an audible and visual alarm BJ. The wiring connections between the components are as follows: Figure 1 As shown.

[0032] This invention modifies the control circuit of the original Dongfeng 5 diesel locomotive by adding an intermediate relay 4ZJ, a time relay SJ3, and an audible and visual alarm BJ. This enables the system to restore the interlocked electromagnet LDT fuel supply when the oil pressure is low, which means that the continuous injection of atomized diesel fuel into the cylinder is restored. Taking advantage of the fact that the diesel engine is still at high speed, the piston in the cylinder continues to compress the atomized diesel fuel until it explodes. The piston pushes the crankshaft to rotate through the connecting rod, restoring the diesel engine to run on its own.

[0033] The existing technology is as follows:

[0034] During diesel engine operation, when the pressure of the diesel engine oil pressure relay 1YJ is higher than 100 kPa, the interlocking electromagnet LDT is energized and engaged, connecting the diesel engine's fuel supply circuit and continuously supplying fuel to the diesel engine, thus maintaining its operation. When the oil pressure relay 1YJ detects that the pressure is lower than 80 kPa at a certain moment, the oil pressure relay 1YJ disconnects, stops supplying power to the interlocking electromagnet LDT, and the interlocking electromagnet LDT cuts off the fuel supply circuit to the diesel engine. There is no longer any oil mist supply to the diesel engine cylinder, and the diesel engine speed gradually decreases until it stops, without outputting any alarm information.

[0035] The main creative idea behind this invention is as follows:

[0036] When the oil pressure relay 1YJ detects that the oil pressure is lower than 80 kPa, if the power supply to the interlocking electromagnet LDT is immediately restored, that is, the oil supply to the diesel engine is immediately restored through the interlocking electromagnet LDT, the cylinder continues to be supplied with atomized diesel. Taking advantage of the fact that the diesel engine is still at high speed and coasting, the piston can compress the atomized diesel, thereby generating an explosion, continuing to make the diesel engine crankshaft rotate, re-establishing oil pressure, and restoring the diesel engine to run on its own.

[0037] In this invention, the specific installation positions and connection relationships of each component are as follows:

[0038] The fuel pump switch 4K is located on the control panel and is controlled by the driver. When the fuel pump switch 4K is closed, the fuel pump continuously supplies fuel to the diesel engine fuel supply line.

[0039] The fuel pump contactor RBC is controlled by the fuel pump switch 4K. After the fuel pump contactor RBC coil is energized, its normally open main contacts close, supplying power to the fuel pump motor, which then supplies fuel to the diesel engine pipeline. Further details are omitted here.

[0040] The interlocking electromagnet LDT is located on the diesel engine. According to the diesel engine design, the fuel supply circuit to the diesel engine can only be activated and thus supply fuel to the injection pump after the interlocking electromagnet LDT is energized. Therefore, the interlocking electromagnet LDT needs to be energized whenever the diesel engine is running. Given the structure of the interlocking electromagnet LDT, prolonged full-voltage energization will cause the coil to burn out and lose its function of controlling the fuel circuit. Therefore, after the diesel engine starts and is running normally, a voltage-reducing resistor Rldt is used to divide the voltage of its coil, reducing the voltage of the interlocking electromagnet LDT and maintaining its engagement.

[0041] The intermediate relay 4ZJ is a differential protection intermediate relay. When the pressure inside the diesel engine crankcase exceeds atmospheric pressure, the intermediate relay 4ZJ activates, cutting off the fuel pump and protecting the diesel engine. The installation and connection of the intermediate relay 4ZJ are existing technology and will not be described in detail.

[0042] The fuel injection pump is installed on the diesel engine. When the crankshaft rotates, it turns the liquid fuel into atomized fuel and injects it into the cylinder. As the piston reciprocates in the cylinder, it compresses the atomized diesel fuel. After the atomized diesel fuel explodes, it pushes the piston to continue moving, driving the diesel engine to run continuously. The position and connection of the fuel injection pump are also existing technology.

[0043] The control principles of each device in this invention are as follows:

[0044] The starting contactor QC is used to drive the starter generator, which in turn drives the diesel engine. 45 seconds after pressing the start button, the main normally open contact of the starting contactor QC engages. The battery drives the starter generator through the main normally open contact of the starting contactor QC, which in turn drives the diesel engine crankshaft and connecting rods via the diesel engine output shaft, causing the piston in the cylinder to reciprocate up and down, igniting the atomized fuel injected into the cylinder. The auxiliary normally open contact of the starting contactor QC (the second normally open switch) also engages 45 seconds after pressing the start button, providing full-voltage power to the interlocking electromagnet LDT. After the diesel engine starts and runs automatically, the driver releases the start button, the starting contactor QC releases, its main normally open contact opens, and it no longer supplies power to the starter generator; its auxiliary normally open contact (the second normally open switch) also opens, no longer providing full-voltage power to the interlocking electromagnet LDT.

[0045] The oil pressure relay 1YJ is installed after the oil filter line of the turbocharger at the highest position of the diesel engine, and monitors the oil pressure after the diesel engine starts in real time. Its normally closed contact (first normally closed switch) is connected in series with the voltage-reducing resistor Rldt of the interlocking electromagnet LDT, and then in parallel with the auxiliary normally open contact (second normally open switch) of the starting contactor QC, which divides the voltage of the interlocking electromagnet LDT to prevent it from burning out due to continuous high voltage. When the oil pressure relay 1YJ detects a pressure lower than 80 kPa, its normally closed contact (first normally closed switch) opens, and the interlocking electromagnet LDT no longer conducts the oil circuit supplying fuel to the diesel engine.

[0046] The anti-shutdown relay FTJ1 monitors the closing status of the oil pressure relay 1YJ contacts after startup, thereby monitoring the oil pressure of the oil pressure relay 1YJ. When the oil pressure of the oil pressure relay 1YJ is higher than 100 kPa and the starting contactor QC is released, the coil of the anti-shutdown relay FTJ1 is energized and closes. When the oil pressure is lower than 80 kPa, the anti-shutdown relay FTJ1 is released; its normally closed contact (the third normally closed switch) and the normally closed contact of the starting contactor QC (the second normally closed switch) together control the coil of the time relay SJ3 to be energized.

[0047] The time relay SJ3 is controlled by the contacts of the starting contactor QC and the anti-stop relay FTJ1. For example... Figure 1 As shown, in the time relay SJ3, point A1 is the positive terminal of the working power supply, point A2 is the negative terminal of the working power supply, and point B1 is the positive terminal of the starting power supply. The time relay SJ3 will only operate within 0-10 seconds of the starting power input when both positive and negative working power supplies are connected simultaneously, and a starting power input is also present. Its auxiliary contacts will close. After 10 seconds, its auxiliary contacts will open. When the starting contactor QC is released, and the oil pressure of the hydraulic relay 1YJ is below 80 kPa, the time relay SJ3 is energized. Its normally open contacts (energized delay switch) will close simultaneously, opening after a 10-second delay to supply power to the anti-stop relay FTJ2.

[0048] The anti-shutdown relay FTJ2's coil is controlled by a time relay SJ3. When the diesel engine starts and the oil pressure of the oil pressure relay 1YJ drops below 80 kPa, i.e., the interlocking electromagnet LDT is de-energized, the normally open contact (energizing delay switch) of the time relay SJ3 closes for 10 seconds, energizing the coil of the anti-shutdown relay FTJ2. The first normally open contact (first normally open switch, closed at this time) of the anti-shutdown relay FTJ2 is connected in parallel to the starting contactor QC auxiliary normally open contact (second normally open switch). Simultaneously with the oil pressure of the oil pressure relay 1YJ dropping below 80 kPa, i.e., the instantaneous de-energization of the interlocking electromagnet LDT, it continuously provides full voltage power to the interlocking electromagnet LDT for 10 seconds, restoring fuel injection pump supply. While the diesel engine is still coasting, it resumes supplying atomized diesel fuel to the cylinders. With the piston reciprocating, the atomized diesel fuel is ignited, restoring the diesel engine to re-establish oil pressure. After the anti-shutdown relay FTJ2 is energized, its second normally open contact (fourth normally open switch) closes, supplying power to the audible and visual alarm BJ.

[0049] The audible and visual alarm BJ continuously provides the driver with an audible and visual alarm signal indicating low oil pressure for 10 seconds when the oil pressure of the oil pressure relay 1YJ is below 80 kPa and the anti-shutdown relays FTJ1 and FTJ2 are engaged. After 10 seconds, its contacts open and the alarm stops.

[0050] The overall control method of the present invention is as follows:

[0051] according to Figure 2 Before starting the diesel engine, the driver's control lever is placed in the zero position, and the oil pump switch and fuel pump switch 4K are closed. The start button is pressed for 45 seconds. During this period, the oil pump continuously provides pre-start lubricating oil pressure to the diesel engine. Within 45 seconds, because the starter contactor QC is not engaged, the diesel engine does not start, and no oil pressure is established. The anti-shutdown relay FTJ1 coil is de-energized and does not engage (the fourth normally closed switch is effective). The time relay SJ3 engages, and the normally open contact (energized delay switch) of the time relay SJ3 engages within 0-10 seconds, causing the anti-shutdown relay FTJ2 to engage. Although the anti-shutdown relay FJT2 engages within 0-10 seconds, the diesel engine is not running at this time, and the main engine oil pump, which rotates with the crankshaft, is not running. Therefore, the main engine oil pump has no oil pressure output, and oil pressure is not established. Consequently, the audible and visual alarm BJ does not receive a valid positive power supply and does not activate. At the same time, the interlocking electromagnet LDT is energized within 0-10 seconds and disconnected within 10-45 seconds. However, the generator does not start within 45 seconds, so the diesel engine will not start prematurely within 0-10 seconds when the time relay SJ3 is engaged.

[0052] according to Figure 3After 45 seconds, the starter contactor QC engages, and the battery provides power to the starter generator, which then drives the diesel engine. On one hand, the fuel pump switch 4K provides full voltage to the interlocking electromagnet LDT through the auxiliary normally open contact of the starter contactor QC (the second normally open switch, which is closed at this time). The interlocking electromagnet LDT conducts, supplying fuel to the diesel engine. After the diesel engine cylinder piston compresses the atomized diesel fuel and explodes in the cylinder, the diesel engine begins to run and builds fuel pressure. On the other hand, the first normally closed contact, the second normally closed contact of the starter contactor QC, the power supply to the time relay SJ3, and the normally open contact of the time relay SJ3 remain open. The second normally closed contact of the anti-shutdown relay FTJ1 (the fourth normally closed switch, which is open at this time) cuts off the positive power to the coil of the anti-shutdown relay FTJ2, so the anti-shutdown relay FTJ2 does not operate. The second normally open contact of the anti-shutdown relay FTJ2 remains open, and the audible and visual alarm BJ does not activate.

[0053] according to Figure 4 If the oil pressure of the hydraulic relay 1YJ exceeds 80 kPa, the diesel engine begins to coast. At this time, releasing the start button stops the start contactor QC from driving the diesel engine. The auxiliary normally open contact (second normally open switch) of the start contactor QC disconnects, no longer providing full voltage to the interlocking electromagnet LDT. The positive power supply passes through the normally closed contact of the intermediate relay 4ZJ, through the contact of the hydraulic relay 1YJ (first normally open switch, now closed), and through the series voltage-reducing resistor Rdls to provide a sustaining voltage to the interlocking electromagnet LDT, continuously maintaining the fuel supply path to the diesel engine. The hydraulic relay 1YJ enables real-time monitoring of the diesel engine oil pressure during operation. When the first normally closed contact (first normally closed switch) of the starting contactor QC closes, the anti-stop relay FTJ1 is energized and engages. Its first normally closed contact (third normally closed switch, which is open at this time) and the second normally closed contact (second normally closed switch) of the starting contactor QC together act on the time relay SJ3. The time relay SJ3 does not operate. The coil of the anti-stop relay FTJ2 is simultaneously de-energized, and its second normally open contact (third normally open switch) opens. The audible and visual alarm BJ does not operate.

[0054] according to Figure 5When the diesel engine starts, if the oil pressure of the oil pressure relay 1YJ drops below 80 kPa at a certain moment, the anti-shutdown relay FTJ1 is de-energized. Its first normally closed contact (third normally closed switch) and the second normally closed contact (second normally closed switch) of the starting contactor QC simultaneously supply power to the time relay SJ3. The normally open contact (energized delay switch) controlled by the time relay SJ3 begins to close, lasting for 10 seconds. On the other hand, the positive current of the anti-shutdown relay FTJ2 is supplied by the second normally closed contact of the FTJ1 coil, and the negative current of the FTJ2 coil is provided by the normally open contact (energized delay switch) controlled by the time relay SJ3. The anti-shutdown relay FTJ2 engages within 10 seconds of the moment the oil pressure of the oil pressure relay 1YJ drops below 80 kPa. Simultaneously, the auxiliary normally open contact of the anti-shutdown relay FTJ2 closes, providing full voltage to the interlocking electromagnet LDT. The interlocking electromagnet LDT then connects the diesel engine's fuel supply circuit. Since the diesel engine is still at high-speed idle, the fuel injection pump continuously injects atomized diesel fuel into the cylinder. Driven by the crankshaft and connecting rod, the piston compresses the atomized diesel fuel, causing it to burst and push the piston, connecting rod, and crankshaft again, thus enabling the diesel engine to start quickly and automatically and re-establish lubricating oil pressure. Simultaneously, the alarm BJ continuously alerts the driver for 10 seconds, informing them of a momentary malfunction.

[0055] according to Figure 6 After the diesel engine oil pressure is established, the anti-shutdown relay FTJ1 engages, the anti-shutdown relay FTJ2 disengages, and the alarm BJ stops sounding after 10 seconds. This device is designed according to... Figures 2-5 The locomotive operates automatically in sequence without human intervention, minimizing the safety risks associated with the locomotive lacking traction power and air braking.

[0056] The parts of this invention not described in detail are prior art.

Claims

1. A quick-start device for the diesel engine of the Dongfeng 5 diesel locomotive after a low-pressure shutdown of the lubricating oil, comprising a fuel pump switch 4K, an intermediate relay 4ZJ, and a fuel pump contactor RBC, characterized in that: One end of the fuel pump switch 4K is connected to the positive terminal of the power supply, and the other end is connected to the normally closed contact of the intermediate relay 4ZJ. The other end of the normally closed contact of the intermediate relay 4ZJ is connected in parallel with the negative terminal of the power supply via a first branch, a second branch, a third branch, and a fourth branch. The fuel pump contactor RBC is connected in series in the first branch. The second branch includes a parallel switch circuit, an interlocking electromagnet LDT, a third normally open switch, and a step-down resistor Rldt. One end of the parallel switch circuit is connected to an intermediate relay 4ZJ, and the other end is connected to the input terminal of the interlocking electromagnet LDT. The input terminal of the third normally open switch is connected to the intermediate relay 4ZJ, and the output terminal is connected to the step-down resistor Rldt. The other end of the step-down resistor Rldt is connected to the input terminal of the interlocking electromagnet LDT. The output terminal of the interlocking electromagnet LDT is connected to the negative terminal of the power supply. The interlocking electromagnet LDT controls the on / off of the fuel supply line of the Dongfeng 5 diesel locomotive's diesel engine. The third normally open switch is the normally open contact of an oil pressure relay 1YJ. The oil pressure relay 1YJ is installed in the pipeline after the oil filter of the turbocharger at the highest position of the Dongfeng 5 diesel locomotive's diesel engine. When the pressure is below 80 kPa, the third normally open switch is open; when the pressure is above 100 kPa, the third normally open switch is closed. The parallel circuit includes a first normally open switch and a second normally open switch, which are connected in parallel. The output terminal of the third normally open switch is connected to a fifth branch, which includes a first normally closed switch and an anti-stop relay FTJ1. The input terminal of the first normally closed switch is connected to the output terminal of the third normally open switch, and the output terminal of the first normally closed switch is connected to the anti-stop relay FTJ1. The other end of the anti-stop relay FTJ1 is connected to the negative terminal of the power supply. The third branch includes a second normally closed switch, a third normally closed switch and a time relay SJ3. The input terminal of the second normally closed switch is connected to the intermediate relay 4ZJ, and the output terminal is connected to the positive terminals of the working power supplies of the third normally closed switch and the time relay SJ3 respectively. The other end of the third normally closed switch is connected to the positive terminal of the starting power supply of the time relay SJ3, and the positive terminal of the working power supply of the time relay SJ3 is connected to the negative terminal of the power supply. The fourth branch includes a fourth normally closed switch, an anti-shutdown relay FTJ2, and a power-on delay switch connected in series. The power-on delay switch is the normally open contact of a time relay SJ3, and the power-on delay time of the power-on delay switch is less than or equal to 10 seconds.

2. The rapid start device for low-pressure lubricating oil protection of the Dongfeng 5 diesel locomotive diesel engine according to claim 1, characterized in that: The second normally open switch, the first normally closed switch, and the second normally closed switch are all controlled by the starting contactor QC. The second normally open switch is the auxiliary normally open contact of the starting contactor QC, the first normally closed switch is the first normally closed contact of the starting contactor QC, and the second normally closed switch is the second normally closed contact of the starting contactor QC. The starting contactor QC is controlled by the locomotive start button. After the locomotive start button is pressed for 45 seconds, the main normally open contact of the starting contactor QC closes, driving the starter generator to rotate. At the same time, the first and second normally closed contacts of the starting contactor QC change from closed to open, and the auxiliary normally open contact changes from open to closed.

3. The rapid start device for low-pressure lubricating oil protection of the Dongfeng 5 diesel locomotive diesel engine according to claim 2, characterized in that: The first normally open switch is the first normally open contact of the anti-stop relay FTJ2.

4. The rapid start device for low-pressure lubricating oil protection of the Dongfeng 5 diesel locomotive diesel engine according to claim 3, characterized in that: The third normally closed switch is the first normally closed contact of the anti-stop relay FTJ1, and the fourth normally closed switch is the second normally closed contact of the anti-stop relay FTJ1.

5. The rapid start device for low-pressure protection of diesel engine lubricating oil in Dongfeng 5 type diesel locomotives according to claim 1, characterized in that: The fifth branch also includes a fourth normally open switch and an audible and visual alarm BJ connected in series. One end of the fourth normally open switch is connected to the output terminal of the first normally closed switch, and the other end is connected to the audible and visual alarm BJ. The other end of the audible and visual alarm BJ is connected to the negative terminal of the power supply. The fourth normally open switch is the second normally open contact of the anti-stop relay FTJ2.

6. The rapid start device for low-pressure lubricating oil protection of the Dongfeng 5 diesel locomotive diesel engine according to claim 1, characterized in that: The power-on delay time of the power-on delay switch is equal to 10 seconds.

Images