CN112081702A - A constant pressure stabilization device for diesel engine preheating system - Google Patents

Abstract

The invention discloses a constant-pressure stabilizing device of a preheating system of a diesel engine, which belongs to the technical field of preheating of the diesel engine and comprises a communicating valve, an oil tank, a low-pressure pump, a diesel fine filter, an electromagnetic valve and a flame jet type preheater, wherein the communicating valve is integrated into a whole structure; diesel oil is finely filtered and flows into a communicating valve, and the communicating valve reduces pressure and flow of the diesel oil and then flows into a flame jet type preheater through an electromagnetic valve for combustion; and the redundant diesel oil flowing into the flame jet type preheater returns to the oil tank after flowing back into the communicating valve through the oil return pipe by the electromagnetic valve. The communicating valve designed in the invention reduces the pressure and limits the flow of the larger diesel oil through the damping hole designed on the oil inlet path, and the one-way valve is added on the oil return path to stabilize the oil pressure and ensure the normal flow direction of the diesel oil, thereby achieving the purpose of keeping the pressure of the oil supply system constant.

Description

A constant pressure stabilization device for diesel engine preheating system

technical field

The invention relates to the technical field of diesel engine preheating, in particular to a constant pressure stabilization device for a diesel engine preheating system, which is applied to a diesel fuel supply pipeline of a flame jet preheater system.

Background technique

The flame preheating system is an important system for the cold start of the diesel engine. The diesel engine belongs to the compression ignition engine and has no spark plug ignition. When the diesel engine is cold started, due to the low initial speed of the diesel engine crankshaft, the diesel is easy to condense. Therefore, during the cold start, it is difficult for the gas entering the cylinder to rise to the auto-ignition temperature, and a preheating device is required to increase the intake air temperature. At present, the main preheating devices for diesel engines are electric heating wire preheaters and flame jet preheaters.

There is no constant pressure stabilization device in the existing diesel engine flame preheating system, which has the following disadvantages:

First, the existing diesel engine preheating system pipelines are mostly used in in-line pump diesel engines and electronically controlled unit pump diesel engines. The low-pressure diesel pipelines of these two types of diesel engines have low pressure, and the pressure and flow are controlled by the working state of the low-pressure pump. There is no oil return pipeline in the preheating system pipeline, and the oil inlet pipeline of the flame jet preheater is directly connected with the low pressure diesel pipeline, and the pressure and flow are controlled by the low pressure pump. During a cold start, the starter motor drives the diesel engine and indirectly provides power for the low-pressure pump. At this time, the speed of the low-pressure pump fluctuates greatly, resulting in a large change in the diesel pressure and flow of the low-pressure pump, which affects the normal operation of the flame glow plug;

Second, on the high-pressure common rail diesel engine, due to the difference in the fuel supply system, the pressure in the low-pressure diesel pipeline is relatively large. If it is directly connected to the oil inlet pipeline of the flame injection preheater, the preheater cannot withstand it, which is easy to cause flame injection. damage to the preheater.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a constant pressure stabilization device for a diesel engine preheating system. The design of the connecting valve is to design a damping hole in the oil inlet path to depressurize and limit the large diesel pressure, and increase the pressure on the oil return path. The one-way valve is used to stabilize the oil pressure and ensure the normal flow direction of diesel oil, so as to achieve the purpose of constant oil supply system pressure. It is used in the diesel fuel supply pipeline of the flame jet preheater system.

For solving the above-mentioned technical problems, the technical scheme adopted in the present invention is:

A constant pressure stabilization device for a diesel engine preheating system, comprising a communication valve integrated into an integrated structure, a fuel tank containing diesel fuel, a low-pressure pump for extracting and pressurizing diesel fuel from the fuel tank, a diesel fine filter for filtering the diesel, and a flame injection control The electromagnetic valve of the oil inlet and return of the preheater and the flame jet preheater in which the diesel fuel is burned; the low pressure pump draws the diesel oil from the fuel tank and pressurizes it, and the pressurized diesel oil flows into the communication valve through the diesel fine filter, The communication valve reduces the pressure and flow of the diesel oil and then flows into the flame jet preheater through the solenoid valve for combustion; the excess diesel oil flowing into the flame jet preheater flows back into the communication valve through the solenoid valve through the oil return pipe and returns to the fuel tank.

A further improvement of the technical solution of the present invention is that the communication valve includes a valve body provided with 5 threaded connection holes, a damping hole for reducing pressure and reducing flow, a sealing bolt for sealing the one-way valve passage, and a steel ball spring structure. One-way valve; the damping hole and the one-way valve work together to realize the function of voltage regulation and current limiting.

A further improvement of the technical solution of the present invention is that: the five threaded connection holes include hole 1, hole 2, hole 3, hole 4 and sealing bolt holes; diesel oil enters from hole 1, passes through the damping hole in the pipeline, and exits from the hole. The second flows into the solenoid valve; then the purpose of pressure reduction and current limiting is achieved, and the return oil enters from the third hole, passes through the one-way valve, and flows out from the fourth hole into the general oil return pipeline.

A further improvement of the technical solution of the present invention is that the damping hole is a full external thread stud, and a small hole is machined in the center.

A further improvement of the technical solution of the present invention is that: the outer diameter of the one-way valve is provided with an external thread, which can be screwed into the sealing bolt hole in the valve body, and the diesel oil can only pass through in one direction and cannot flow in the reverse direction.

The further improvement of the technical solution of the present invention is that the communication valve can reduce the pressure of the low-pressure diesel oil pipeline from 7-10 bar to 2-3 bar before the diesel oil enters the solenoid valve.

A further improvement of the technical solution of the present invention is that the opening pressure of the one-way valve is 2-3 bar.

A further improvement of the technical solution of the present invention is that the low-pressure pump draws out the diesel oil from the fuel tank and pressurizes it to 7-10 bar.

A further improvement of the technical solution of the present invention is that the communication valve shell and valve body are of an aluminum alloy cuboid structure.

Owing to having adopted the above-mentioned technical scheme, the technical progress that the present invention obtains is:

1. The present invention reduces the pressure and restricts the large diesel pressure by designing a damping hole in the oil inlet circuit, and adds a check valve on the oil return road to stabilize the oil pressure and ensure the normal flow direction of the diesel oil, so as to achieve a constant The purpose of the oil supply system pressure.

2. The present invention integrates the oil inlet and oil return pipelines of the preheating system into a communication valve, uses a simple mechanical structure, and realizes the functions of depressurization, current limiting and voltage stabilization without using electronic control. .

3. The present invention integrates two kinds of oil inlet decompression and oil return pressure maintaining devices, which is convenient for arrangement and installation. It is one of the key components of the diesel engine preheating diesel supply system, and directly solves most of the current flame preheating systems. There is no problem of oil return device and voltage stabilization device, which is not only suitable for high diesel pressure applications, but also can play the role of voltage stabilization and current limiting, which is conducive to the normal operation of the flame preheating system.

4. The communication valve in the present invention is highly integrated, occupies less space in the diesel engine, is light in weight, and does not use an electronic system, which achieves the purpose of voltage regulation and current limiting, and is applied to the diesel supply pipeline of the flame jet preheater system, which can solve the problem. The problem of stabilizing diesel pressure and balancing diesel flow in the flame preheating diesel pipeline of high pressure common rail diesel engine.

Description of drawings

Fig. 1 is the connection schematic diagram of the constant pressure stabilization device of the preheating system of the present invention;

2 is a schematic diagram of the internal structure of the communication valve of the present invention;

Figure 3 is a schematic diagram of the installation of the present invention in a diesel engine.

Among them, 1. Connecting valve, 1-1, valve body, 1-2, hole 2, 1-3, damping hole, 1-4, hole 1, 1-5, sealing bolt, 1-6, one-way valve, 1-7, hole four, 1-8, hole three, 2, fuel tank, 3, low pressure pump, 4, diesel fine filter, 5, solenoid valve, 6, flame jet preheater, 7, connecting valve to preheat Solenoid valve inlet oil, 8. Glow plug oil return to the connecting valve, 9. Oil return to the fuel injection pump total return, 10. Preheat solenoid valve oil inlet, 11. Oil pipe to the flame glow plug, 12. Glow plug return tubing.

Detailed ways

In view of the shortcomings in the prior art, the present invention develops a constant pressure stabilization device for a diesel engine preheating system. An oil inlet pipeline and an oil return pipeline are arranged inside the communication valve, and the two pipelines operate independently without interfering with each other, which can realize the In the high-pressure common-rail diesel engine preheating system, the function of reducing the oil inlet pressure and flow and stabilizing the oil pressure of the oil supply pipeline to ensure the normal flow of diesel flow problem.

Below in conjunction with accompanying drawing, the present invention is described in further detail:

As shown in Figure 1, a constant pressure stabilization device for a diesel engine preheating system includes a communication valve 1 integrated into an integrated structure, a fuel tank 2 containing diesel fuel, a low pressure pump 3 for extracting and pressurizing diesel fuel from the fuel tank 2, The diesel fine filter 4 for filtering, the solenoid valve 5 for controlling the oil inlet and return of the flame jet preheater 6, and the flame jet preheater 6 in which the diesel fuel is burned; the low pressure pump 3 draws the diesel oil from the fuel tank 2 and Pressurized, the pressurized diesel oil flows into the communication valve 1 through the diesel fine filter 4, and the communication valve 1 reduces the pressure and flow of the diesel oil, and then flows into the flame jet preheater 6 through the solenoid valve 5 for combustion; flows into the flame jet preheater. The excess diesel oil in the device 6 flows back into the communication valve 1 through the solenoid valve 5 through the oil return pipe and then returns to the fuel tank 2 .

As shown in FIG. 2 , the communication valve 1 includes a valve body 1-1 provided with 5 threaded connection holes, a damping hole 1-3 for reducing pressure and flow, and a valve for sealing the passage of the one-way valve 1-6. The sealing bolts 1-5 and the one-way valve 1-6 of the steel ball spring structure; the damping hole 1-3 and the one-way valve 1-6 work together to realize the function of voltage regulation and current limiting.

The five threaded connection holes include hole one 1-4, hole two 1-2, hole three 1-8, hole four 1-7 and sealing bolt holes. Diesel enters from hole one 1-4 and passes through the pipeline. After the damping holes 1-3 are opened, the purpose of pressure reduction and current limitation is achieved, and the oil flows into the solenoid valve 5 from the hole 2 1-2; the return oil enters from the hole 3 1-8, passes through the check valve 1-6, and flows from the hole 4 1-7. Outflow into the main oil return line.

The damping holes 1-3 are fully externally threaded studs with small holes machined in the center. act as damping.

The outer diameter of the one-way valve 1-6 is provided with an external thread, which can be screwed into the sealing bolt hole in the valve body 1-1, and the diesel oil can only pass through in one direction, and cannot flow in the reverse direction.

The communication valve 1 can reduce the pressure of the low-pressure diesel pipeline from 7-10bar to 2-3bar before the diesel oil enters the solenoid valve 5.

The opening pressure of check valve 1-6 is 2-3bar.

Low pressure pump 3 draws diesel fuel from tank 2 and pressurizes it to 7-10bar.

The outer casing and valve body of the communication valve 1 is an aluminum alloy cuboid structure.

working principle:

1. Functional principle description

The diesel engine preheating system is mainly used to preheat the diesel engine when the diesel engine is started in a low temperature environment. Its main components are flame glow plugs, control systems, and diesel supply systems. , The diesel supply system is controlled by the control system to supply diesel with suitable pressure and flow at the right time, and it is ignited by the flame glow plug to achieve the purpose of heating the intake air of the diesel engine, thereby facilitating the diesel engine to start in a low temperature environment.

When the diesel engine starts at a low temperature, the low-pressure pump 3 starts to work, and the diesel oil is pumped out from the fuel tank 2 and pressurized to 7-10bar and sent to the diesel fine filter 4 for filtration. After hole 1-3 is depressurized and flow-reduced, it is sent to solenoid valve 5 by hole 2 1-2. After solenoid valve 5 is opened, diesel fuel enters flame jet preheater 6 for combustion to heat the intake air, and excess diesel oil passes through the oil return pipe. Entering hole three 1-8, diesel oil returns to tank 2 from hole four 1-7 after passing through check valve 1-6.

There are two main functions of the communication valve 1:

First, before the diesel enters the solenoid valve 5, reduce the pressure and flow of the low-pressure diesel pipeline, reduce the pressure of the low-pressure diesel pipeline from 7-10bar to 2-3bar, so as to protect the mechanical structure of the solenoid valve 5 and the flame jet preheating. the purpose of device 6.

Second, ensure that the diesel fuel in the preheating system can return to the main oil return pipe, but the diesel oil in the main oil return pipe cannot enter the preheating system to ensure the normal flow direction of the diesel oil and prevent the flame glow plug from leaking oil due to the oil return.

2. Structural principle description

As shown in Figure 2, the outer casing and valve body of the communication valve 1 is an aluminum alloy cuboid structure with 5 threaded connection holes. The damping holes 1-3 are full external threaded studs, and a small hole is machined in the center to play a damping role. Check valves 1-6 are steel ball spring structures with external threads on the outer diameter, which can be screwed into the valve body. Diesel oil can only pass in one direction and cannot flow in the opposite direction. The sealing plugs 1-5 seal the channels 1-6 of the one-way valve. Diesel enters from hole one 1-4, and passes through the orifice 1-3 in the pipeline to achieve the purpose of depressurization and current limiting, and the return oil enters from hole three 1-8, through the oil return check valve 1 opened at 2-3bar -6, flow out from holes 4 1-7 into the general oil return pipeline, to achieve the purpose of stabilizing the diesel pressure, and prevent the diesel in the fuel tank 2 from backflowing into the preheating pipeline.

As shown in Figure 3, the schematic diagram of the installation position of the communication valve 1 in the diesel engine, the communication valve goes to the preheating solenoid valve to feed oil 7, the glow plug returns oil to the communication valve 8, returns the oil to the fuel injection pump return 9, and the preheating solenoid valve Oil inlet 10, to flame glow plug oil pipe 11, glow plug return oil pipe 12.

To sum up, the communication valve designed in the present invention is highly integrated. By designing a damping hole in the oil inlet path to reduce the pressure and limit the current of the large diesel oil, a check valve is added on the oil return path to stabilize the oil pressure and the flow rate. Ensure the normal flow direction of diesel oil, so as to achieve the purpose of constant fuel supply system pressure; the connecting valve occupies less space in the diesel engine, is light in weight, and does not use an electronic system to achieve the purpose of voltage regulation and current limiting, and is used in the flame jet preheater system It can solve the problem of stabilizing the diesel pressure and balancing the diesel flow in the flame preheating diesel pipeline of the high-pressure common rail diesel engine.

Claims (9)

1. The utility model provides a constant voltage stabilising arrangement of diesel engine preheating system which characterized in that: the diesel oil purifier comprises a communication valve (1) integrated into a whole, an oil tank (2) for containing diesel oil, a low-pressure pump (3) for pumping out and pressurizing the diesel oil from the oil tank (2), a diesel oil fine filter (4) for filtering the diesel oil, an electromagnetic valve (5) for controlling oil inlet and return of a flame jet type preheater (6) and the flame jet type preheater (6) for burning the diesel oil in the flame jet type preheater; the low-pressure pump (3) pumps diesel oil out of the oil tank (2) and pressurizes the diesel oil, the pressurized diesel oil flows into the communicating valve (1) through the diesel oil fine filtration (4), the communicating valve (1) reduces the pressure and the flow of the diesel oil, and then the diesel oil flows into the flame jet type preheater (6) through the electromagnetic valve (5) to be combusted; and the redundant diesel oil flowing into the flame jet type preheater (6) returns to the communicating valve (1) through an oil return pipe by the electromagnetic valve (5) and then returns to the oil tank (2).

2. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the communication valve (1) comprises a valve body (1-1) provided with 5 threaded connecting holes, a damping hole (1-3) for reducing pressure and flow, a sealing bolt (1-5) for sealing a channel of the check valve (1-6) and a check valve (1-6) with a steel ball spring structure; the damping holes (1-3) and the one-way valves (1-6) work together to realize the functions of stabilizing pressure and limiting flow.

3. The constant-pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 2, wherein: the 5 threaded connecting holes comprise a first hole (1-4), a second hole (1-2), a third hole (1-8), a fourth hole (1-7) and a sealing bolt hole; diesel oil enters from the first hole (1-4), passes through the damping hole (1-3) in the pipeline and flows into the electromagnetic valve (5) from the second hole (1-2); return oil enters from the third hole (1-8), flows out from the fourth hole (1-7) through the one-way valve (1-6) and enters a main oil return pipeline.

4. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the damping hole (1-3) is a full external thread stud, and a small hole is processed in the center.

5. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the outer diameter of the one-way valve (1-6) is provided with external threads, the one-way valve can be screwed into a sealing bolt hole in the valve body (1-1), and diesel oil can only pass through in one way and cannot flow in the reverse direction.

6. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the communicating valve (1) can reduce the pressure of a low-pressure diesel pipeline from 7-10bar to 2-3bar before diesel enters the electromagnetic valve (5).

7. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the opening pressure of the one-way valve (1-6) is 2-3 bar.

8. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the low-pressure pump (3) draws the diesel oil from the oil tank (2) and pressurizes the diesel oil to 7-10 bar.

9. The constant pressure stabilizing device of a preheating system of a diesel engine as set forth in claim 1, wherein: the shell valve body of the communicating valve (1) is of an aluminum alloy cuboid structure.

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