A kind of automatic recovery device for monomer pump diesel engine leakage fuel

Abstract

The utility model discloses a kind of single pump diesel engine leakage fuel automatic recovery device, it is related to diesel engine, solve the technical problem that short period is easily caused in the liquid level sensing module of existing fuel oil automatic recovery device electric oil pump frequent start-stop.It includes electric oil pump and oil tank, the top of the oil tank is provided with oil return inlet, the electric oil pump is installed in the outside of oil tank and the oil pumping end of electric oil pump is communicated with the oil outlet of oil tank, the device further includes timing control circuit, the timing control circuit is electrically connected with electric oil pump, and the timing control circuit is equipped with alarm module.The utility model avoids the situation that electric oil pump frequent start-stop is caused by vehicle movement, temperature change etc. Frequent fluctuation, ensure the stable operation of electric oil pump, avoid invalid action.

Description

Technical Field

[0001] This utility model relates to diesel engines, and more specifically, to an automatic fuel recovery device for a unit pump diesel engine. Background Technology

[0002] The purpose of the fuel spill collection tank is to collect and store the return fuel generated by the fuel pump. The mechanism of this return fuel generation is explained below:

[0003] The plunger and plunger sleeve are precision-fitted components with a clearance of 2-10 micrometers. During operation, the high-pressure fuel generated at the top of the plunger can reach over 1000 kg. This high-pressure fuel leaks downwards through the plunger assembly clearance to the zero-backpressure fuel return passage, where it is discharged. Simultaneously, the pump's cam chamber is filled with engine oil. During operation, the pump roller assembly converts the camshaft's rotational motion into the plunger's vertical linear motion. This rapid up-and-down movement of the plunger scrapes upwards the engine oil. The oil carried upwards through the plunger clearance mixes with the leaking diesel fuel as it flows through the zero-backpressure fuel return passage (see...). Figure 1 The diagram shows the oil return passage structure of the engine unit pump. On the other hand, the oil carried in by the lower surface of the plunger can also prevent the plunger from sticking due to insufficient lubrication.

[0004] To prevent diesel fuel and engine oil from mixing, and to protect the engine and fuel pump, we have adopted a fuel return port design in the large-diameter plunger fuel pump to isolate and drain the leaking part. Currently, Bosch and MAN both domestically and internationally use this structure in their marine electric fuel systems.

[0005] The reason why manually draining the fuel leak collection tank is inconvenient is that the return fuel from the unit pump flows into the fuel leak collection tank, which has a limited capacity. When a large amount of sludge is observed through the liquid level observation tube, the drain valve needs to be opened manually to remove the return fuel. If the sludge is not removed in time, leaked fuel will overflow from the vent at the top of the collection tank.

[0006] The prior art discloses a fuel recovery device that obtains the fuel level in the tank through a liquid level sensing module and adjusts the start and stop of the electric fuel pump according to the fuel level. It can remove waste oil in a timely manner according to the fuel level. However, the fuel level may fluctuate frequently due to environmental factors such as vehicle movement and temperature changes. The liquid level sensing module may be falsely triggered, which can easily lead to frequent start and stop of the electric fuel pump in a short period of time. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide an automatic fuel recovery device for leaking diesel engines with a single pump, which addresses the shortcomings of the existing technology and solves the technical problem that the liquid level sensing module in the existing automatic fuel return recovery device easily leads to frequent start-stop of the electric oil pump within a short period of time.

[0008] The present invention discloses an automatic fuel recovery device for a single-unit pump diesel engine, which includes an electric oil pump and an oil tank. The top of the oil tank has an oil return inlet. The electric oil pump is installed on the outside of the oil tank and its pumping end is connected to the oil outlet of the oil tank. The device also includes a timing control circuit, which is electrically connected to the electric oil pump and has an alarm module.

[0009] As a further improvement, the timing control circuit includes a power supply, a double-pole double-throw relay, a first time relay, and a second time relay;

[0010] The positive terminal of the power supply is electrically connected to the first common terminal of the double-pole double-throw relay, and the first normally closed terminal of the double-pole double-throw relay is electrically connected to the coil of the first time relay and the normally open switch of the first time relay, respectively.

[0011] The first normally open terminal of the double-pole double-throw relay is electrically connected to the coil of the second time relay and the normally open switch of the second time relay, respectively.

[0012] The normally open switch of the first time relay and the normally open switch of the second time relay are both electrically connected to the motor of the electric oil pump. The coil of the first time relay and the coil of the second time relay are both electrically connected to the motor of the electric oil pump. The motor of the electric oil pump is electrically connected to the negative terminal of the power supply.

[0013] The coil of the double-pole double-throw relay is electrically connected to the ECU.

[0014] Furthermore, the alarm module includes a level switch and an alarm light. The level switch is electrically connected to the positive terminal of the power supply, the level switch is electrically connected to the alarm light, the alarm light is electrically connected to the negative terminal of the power supply, and the level switch is fixedly installed on the inner wall of the oil tank.

[0015] Furthermore, a filter is installed below the oil return inlet, and the height of the level switch is higher than the bottom of the filter.

[0016] Furthermore, the electric oil pump is equipped with a manual drain valve at its bottom.

[0017] Furthermore, the oil tank is equipped with a pressure relief valve.

[0018] Beneficial effects

[0019] The advantages of this utility model are:

[0020] This utility model includes an electric oil pump and an oil tank. The top of the oil tank has a return oil inlet. The electric oil pump is installed on the outside of the oil tank, and its suction end is connected to the oil outlet of the oil tank. The device also includes a timing control circuit, which is electrically connected to the electric oil pump. The timing control circuit is equipped with an alarm module to effectively collect and process the fuel return from the engine, reducing environmental pollution and meeting environmental regulations. Compared with the existing liquid level sensing module that controls the start and stop of the electric oil pump, this invention avoids frequent start and stop of the electric oil pump due to frequent fluctuations such as vehicle movement and temperature changes, ensuring stable operation of the electric oil pump and avoiding ineffective actions. Attached Figure Description

[0021] Figure 1 A schematic diagram of fuel leakage in the existing unit pump return oil passage structure of an engine.

[0022] Figure 2 This is a schematic diagram of the automatic fuel recovery device for a single-pump diesel engine according to the present invention.

[0023] Figure 3 This is a schematic diagram of the timing control circuit for the automatic fuel recovery device for a single-pump diesel engine according to this utility model.

[0024] Among them: 1-electric oil pump, 2-oil tank, 3-oil return inlet, 4-pressure relief valve, 5-filter, 6-manual oil drain valve, U1-power supply, KM-double-pole double-throw relay, KT1-first time relay, KT2-second time relay, KA1-normally open switch of the first time relay, KA2-normally open switch of the second time relay, KM1-first normally closed terminal of the double-pole double-throw relay, KM2-first normally open terminal of the double-pole double-throw relay, L-alarm light, KS-level switch, G-motor of the electric oil pump. Detailed Implementation

[0025] The present invention will be further described below with reference to embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0026] See Figures 2-3 This utility model discloses an automatic fuel recovery device for leaking diesel engines with a single pump. It includes an electric oil pump 1 and an oil tank 2. The top of the oil tank 2 is provided with an oil return inlet 3. The electric oil pump 1 is installed on the outside of the oil tank 2 and the oil pump end of the electric oil pump 1 is connected to the oil outlet of the oil tank 2. The device also includes a timing control circuit, which is electrically connected to the electric oil pump 1. The timing control circuit is equipped with an alarm module.

[0027] like Figure 3As shown, the timing control circuit includes a power supply U1, a double-pole double-throw relay KM, a first time relay KT1, and a second time relay KT2.

[0028] The positive terminal of power supply U1 is electrically connected to the common terminal of double-pole double-throw relay KM. The first normally closed terminal KM1 of the double-pole double-throw relay is electrically connected to the coil of the first time relay KT1 and the normally open switch KA1 of the first time relay.

[0029] The first normally open terminal KM2 of the double-pole double-throw relay is electrically connected to the coil of the second time relay KT2 and the normally open switch KA2 of the second time relay.

[0030] The normally open switch KA1 of the first time relay and the normally open switch KA2 of the second time relay are both electrically connected to the motor G of the electric oil pump. The coil of the first time relay KT1 and the coil of the first time relay KT1 are both electrically connected to the motor G of the electric oil pump. The motor G of the electric oil pump is electrically connected to the negative terminal of the power supply U1.

[0031] The coil of the double-pole double-throw relay KM is electrically connected to the ECU.

[0032] The alarm module includes a level switch KS and an alarm light L. The level switch KS is electrically connected to the positive terminal of the power supply U1, the level switch KS is electrically connected to the alarm light L, and the alarm light L is electrically connected to the negative terminal of the power supply U1. The level switch KS is fixedly installed on the inner wall of the oil tank 2.

[0033] A filter 5 is installed below the return oil inlet 3, and the level switch KS is higher than the bottom of the filter 5. When the sludge level in the oil tank 2 gradually exceeds the level switch KS, the level switch KS closes, the alarm light L is energized and illuminates, thus reminding the operator to open the manual drain valve 6. The oil in the oil tank 2 is then drained from the manual drain valve 6, thus ensuring that the sludge does not overflow from the return oil inlet 3.

[0034] The bottom of the electric oil pump 1 is equipped with a manual drain valve 6. The manual drain valve 6 enables rapid and controllable discharge of oil by manual operation.

[0035] The oil tank 2 is equipped with a pressure relief valve 4. The function of the pressure relief valve 4 is to automatically open and release pressure when the pressure inside the oil tank 2 exceeds the set pressure, so as to ensure that the fuel pressure inside the oil tank 2 is below the set pressure, protect the oil tank 2 and prevent accidents.

[0036] The working principle of this utility model is as follows:

[0037] Obtain the leakage return oil flow rate Q1 of the unit pump when the engine is stationary (engine not running), and calculate the time T1 for the return oil to flow into the oil tank 2 and fill it based on the leakage return oil flow rate Q1 when the engine is stationary.

[0038]

[0039] Where V1 is the volume of oil tank 2 when it is full of oil, and Q1 is the leakage return flow rate of the unit pump when the engine is stationary.

[0040] Obtain the leakage return oil flow rate Q2 of the unit pump under full engine load, and calculate the time T2 for the oil tank 2 to be filled based on the leakage return oil flow rate Q2 under full engine load:

[0041]

[0042] Where V1 is the volume of oil tank 2 when it is full of oil, and Q2 is the leakage return flow rate of the unit pump under full engine load.

[0043] Obtain the oil flow rate Q3 of electric oil pump 1, and calculate the working time T3 of electric oil pump 1 based on the full volume V1 of oil tank 2 and the oil flow rate Q3.

[0044]

[0045] Where V1 is the volume of oil tank 2 when it is full of oil, and Q3 is the oil flow rate of electric oil pump 1.

[0046] When the engine is stationary (not running), the ECU does not energize the coil of the double-pole double-throw relay KM. The first normally closed terminal KM1 of the double-pole double-throw relay is closed, and the first normally open terminal KM2 of the double-pole double-throw relay is open. When the first normally closed terminal KM1 of the double-pole double-throw relay is closed, the coil of the first time relay KT1 is energized. After the first time relay KT1 is energized, the normally open switch KA1 of the first time relay closes, energizing the motor G of the electric oil pump, and the electric oil pump 1 starts working, and the sludge oil is drawn out from the oil outlet of the oil tank 2. After the first time relay KT1 closes for time T3, the normally open switch KA1 of the first time relay opens, the motor G of the electric oil pump is de-energized, and the electric oil pump 1 stops working. The first time relay KT1 then starts closing for time T1. After time T1 ends, the normally open switch KA1 of the first time relay closes again for time T3, thus forming a periodic cycle. That is, the first time relay KT1 is set to a cycle mode of closing time T3 and opening time T1, and the electric oil pump 5 is set to a cycle mode of working time T3 and closing time T1, thereby realizing the intermittent operation of the electric oil pump 1.

[0047] When the engine is running, the ECU energizes the coil of the double-pole double-throw relay KM, causing the first normally closed terminal KM1 of the double-pole double-throw relay to open and the normally open terminal KM2 of the double-throw relay switch to close. When the normally open terminal KM2 of the double-throw relay switch is closed, the coil of the second time relay KT2 is energized. After the coil of the second time relay KT2 is energized, the normally open switch KA2 of the second time relay first closes, energizing the motor G of the electric oil pump, and the electric oil pump 1 starts to work, and the sludge oil is drawn out from the oil outlet of the oil tank 2. After the second time relay KT2 closes for time T3, the normally open switch KA2 of the second time relay opens, the motor G of the electric oil pump is de-energized, the electric oil pump 1 stops working, and the second time relay KT2 starts to open for time T2. After the time T2 ends, the normally open switch KA2 of the second time relay closes again for time T3, thus forming a periodic cycle. That is, the second time relay KT2 is set to a cycle mode of closing time T3 and opening time T2, and the electric oil pump 5 is set to a cycle mode of working time T3 and closing time T2, thereby realizing the intermittent operation of the electric oil pump 1.

[0048] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present utility model. These modifications and improvements will not affect the effectiveness of the present utility model or the practicality of the patent.

Claims

1. An automatic fuel recovery device for leaking diesel engine with a single pump, comprising an electric oil pump (1) and an oil tank (2), wherein the top of the oil tank (2) is provided with a return oil inlet (3), the electric oil pump (1) is installed on the outside of the oil tank (2) and the oil pump (1) is connected to the oil outlet of the oil tank (2), characterized in that, The device also includes a timing control circuit, which is electrically connected to the electric oil pump (1) and is equipped with an alarm module.

2. A device for automatic recovery of leaked fuel from a single-piston pump diesel engine according to claim 1, characterized in that The timing control circuit includes a power supply (U1), a double-pole double-throw relay (KM), a first time relay (KT1), and a second time relay (KT2); The positive terminal of the power supply (U1) is electrically connected to the first common terminal of the double-pole double-throw relay (KM), and the first normally closed terminal (KM1) of the double-pole double-throw relay is electrically connected to the coil of the first time relay (KT1) and the normally open switch (KA1) of the first time relay. The first normally open terminal (KM2) of the double-pole double-throw relay is electrically connected to the coil of the second time relay (KT2) and the normally open switch (KA2) of the second time relay. The normally open switch (KA1) of the first time relay and the normally open switch (KA2) of the second time relay are both electrically connected to the motor (G) of the electric oil pump. The coil of the first time relay (KT1) and the coil of the first time relay (KT1) are both electrically connected to the motor (G) of the electric oil pump. The motor (G) of the electric oil pump is electrically connected to the negative terminal of the power supply (U1). The coil of the double-pole double-throw relay (KM) is electrically connected to the ECU.

3. A device for automatic recovery of leaked fuel from a single-piston pump diesel engine according to claim 2, characterized in that The alarm module includes a level switch (KS) and an alarm light (L). The level switch (KS) is electrically connected to the positive terminal of the power supply (U1), the level switch (KS) is electrically connected to the alarm light (L), and the alarm light (L) is electrically connected to the negative terminal of the power supply (U1). The level switch (KS) is fixedly installed on the inner wall of the oil tank (2).

4. A device for automatic recovery of leaked fuel from a single-piston pump diesel engine according to claim 3, characterized in that, A filter (5) is installed below the oil return inlet (3), and the height of the liquid level switch (KS) is higher than the bottom of the filter (5).

5. The automatic fuel recovery device for a single-pump diesel engine according to claim 1, characterized in that, The electric oil pump (1) is equipped with a manual drain valve (6) at its bottom.

6. A device for automatic recovery of leaked fuel from a single-pump diesel engine according to claim 1, characterized in that, The oil tank (2) is equipped with a pressure relief valve (4).

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