A diesel engine thermal management control system and method

Abstract

The present invention discloses a diesel engine thermal management control system, which belongs to the field of diesel engine thermal management technology, and solves the technical problem that the working mode of the existing exhaust brake valve cannot meet the requirements or the cost of using an electronically controlled exhaust brake valve is high. The system includes an adjustment frame, an adjustment bolt, an exhaust brake valve, and a controller. The adjustment bolt is fixedly installed on the adjustment frame, the exhaust brake valve is installed on the exhaust pipe and electrically connected to the controller, the valve stem of the exhaust brake valve is provided with a limit baffle corresponding to the position of the adjustment bolt, an opening adjustment plate is provided between the adjustment bolt and the valve stem, the adjustment frame is provided with a driving mechanism for driving the opening adjustment plate to rotate, and the driving mechanism is electrically connected to the controller. The present invention also discloses a diesel engine thermal management control method. The present invention arranges an opening adjustment plate on the adjustment frame, and adjusts the rotation angle of the limit baffle by the opening adjustment plate and the adjustment bolt, thereby adjusting the opening of the exhaust brake valve, with low modification cost and good effect.

Description

Technical Field

[0001] The present invention relates to the technical field of diesel engine thermal management, and more specifically, to a diesel engine thermal management control system and method. Background Art

[0002] Traditional system with mechanical exhaust brake valve (mechanical exhaust throttle valve) such as Figure 1 The exhaust brake valve A is installed on the exhaust pipe G. When the vehicle is operating normally, the exhaust brake valve A is in full-open mode. The position of the valve plate B of the exhaust brake valve A is as shown in the figure. Figure 2 As shown, the engine works normally to drive the vehicle. When the vehicle is sliding downhill (switch signal input, throttle opening is 0), the engine closes the exhaust brake valve A to cut off the exhaust (the exhaust pipe is not completely closed at this time, but the valve plate is in a completely closed state), and the position of the valve plate B of the exhaust brake valve A is as shown in the figure. Figure 3 As shown in the figure, the engine is in braking mode and absorbs the inertial energy of the vehicle going downhill. When the exhaust brake valve A is closed, the position of the valve plate B is determined by adjusting the position of the bolt C, as shown in the figure. Figure 4 As shown, the adjusting bolt C is installed on the adjusting frame F, and a limit baffle E is provided on the valve stem D of the exhaust brake valve A. When the exhaust brake valve A is closed, the valve stem D drives the limit baffle E to rotate to the position of the adjusting bolt C. The position of the adjusting bolt C is obtained based on the bench test. Once the position of the adjusting bolt C is determined, it will be fixed.

[0003] The main function of the exhaust brake valve is to increase exhaust resistance and improve the auxiliary braking performance of the vehicle. In order to meet the braking power requirements of the whole vehicle, the exhaust brake valve is closed to achieve high braking performance. The interception effect of the exhaust brake valve is very strong when it is closed, resulting in insufficient fresh air replenishment to the engine, and the engine cannot burn normally in normal operation mode. Therefore, the traditional exhaust brake system cannot use the exhaust butterfly valve to perform engine exhaust thermal management, improve the utilization rate of post-treatment, and reduce engine pollutant emissions. The engine can only reduce the amount of air entering the engine through the intake throttle valve. However, using the intake throttle valve to intercept and achieve a strong interception effect will cause a large negative pressure in the intake throttle valve and the cylinder, which will increase the engine oil consumption and affect the operation of the vehicle. In addition, engines using traditional exhaust butterfly valve systems are subject to negative pressure restrictions downstream of the intake throttle valve, and have limited thermal management capabilities. For operational vehicles running at low speeds and low loads, when the carbon soot captured in the DPF reaches the capture upper limit, effective regeneration cannot be achieved during the operation process, requiring customers to press the parking regeneration switch on the spot and increase the engine speed to achieve parking regeneration (the parking regeneration time is generally 20 to 40 minutes), affecting the customer's attendance rate.

[0004] In order to solve the problems of traditional mechanical exhaust brake valves, an electronically controlled exhaust throttle valve with fully controllable valve plate position can be used to replace the traditional mechanical exhaust brake valve. By intelligently controlling the opening of the exhaust butterfly valve through the ECU, efficient exhaust brake function and engine thermal management can be achieved. However, due to the high exhaust temperature, in order to prevent the electrical components of the electronically controlled exhaust brake valve from being damaged by high temperature, a complex structural design or a cooling device is required to cool the exhaust butterfly valve, resulting in high cost of the electronically controlled exhaust brake valve and insignificant economic effect. Summary of the invention

[0005] The technical problem to be solved by the present invention is to address the above-mentioned deficiencies in the prior art. One purpose of the present invention is to provide a diesel engine thermal management control system.

[0006] A second objective of the present invention is to provide a diesel engine thermal management control method.

[0007] In order to achieve the above-mentioned purpose one, the present invention provides a diesel engine thermal management control system, including an adjustment frame, an adjustment bolt, an exhaust brake valve, and a controller, the adjustment bolt is fixedly mounted on the adjustment frame, the exhaust brake valve is mounted on the exhaust pipe and electrically connected to the controller, the valve stem of the exhaust brake valve is provided with a limit baffle corresponding to the position of the adjustment bolt, an opening adjustment plate is provided between the adjustment bolt and the valve stem, the adjustment frame is provided with a driving mechanism for driving the opening adjustment plate to rotate, and the driving mechanism is electrically connected to the controller.

[0008] As a further improvement, the adjustment frame is an L-shaped structure, the adjustment bolt is fixedly mounted on a right angle side of the adjustment frame, and the valve stem of the exhaust brake valve passes through the other right angle side of the adjustment frame.

[0009] Furthermore, the opening adjustment plate is a structure with a small thickness on one side and a large thickness on the other side.

[0010] Furthermore, the opening adjustment plate is composed of at least two shift plates with different thicknesses connected in sequence.

[0011] Furthermore, the driving mechanism is a motor, and a rotating shaft of the motor is connected to one end of the opening adjustment plate.

[0012] Furthermore, the driving mechanism is an electromagnet, one end of the opening adjustment plate is rotatably connected to the adjustment frame via a rotating shaft, one end of the rotating shaft is provided with an adsorption rod corresponding to the adsorption end of the electromagnet, and the adsorption rod is provided with a reset spring connected to the adjustment frame.

[0013] Furthermore, the driving mechanism is a cylinder or a hydraulic cylinder or an electric push rod, one end of the opening adjustment plate is rotatably connected to the adjustment frame through a rotating shaft, one end of the rotating shaft is provided with a connecting rod, and both ends of the driving mechanism are rotatably connected to the connecting rod and the adjustment frame respectively.

[0014] Furthermore, the controller is an ECU.

[0015] In order to achieve the above-mentioned second objective, the present invention provides a diesel engine thermal management control method, comprising the following steps:

[0016] Step S1. The controller obtains the engine speed, throttle opening, actual exhaust temperature and exhaust brake request switch signal;

[0017] Step S2. If the exhaust brake request switch is pressed, execute step S3; otherwise, execute step S5;

[0018] Step S3. If the throttle opening is equal to 0, execute step S4; otherwise, execute step S5;

[0019] Step S4. Enter the braking working mode, the controller controls the driving mechanism to reset and the exhaust brake valve to close, the opening adjustment plate rotates away from the adjustment bolt, the limit stopper contacts the adjustment bolt, the valve plate is in the fully closed position, and step S1 is continued;

[0020] Step S5. The controller calculates the exhaust temperature corresponding to the target torque according to the engine speed and the throttle opening;

[0021] Step S6. If the exhaust temperature corresponding to the target torque exceeds the first temperature or the actual exhaust temperature far exceeds the first temperature, execute step S9; otherwise, execute step S7;

[0022] Step S7. If the exhaust temperature corresponding to the target torque is lower than the first temperature and the actual exhaust temperature is lower than the second temperature and the duration is longer than the set time, then execute step S8; otherwise, execute step S9;

[0023] Step S8. Enter the thermal management working mode, the controller controls the driving mechanism to work and the exhaust brake valve to close, the opening adjustment plate rotates to the adjustment bolt, the limit stopper contacts the opening adjustment plate, the valve plate is in the adjustment position, and step S1 is continued;

[0024] Step S9. Enter the normal working mode, the controller controls the driving mechanism to reset and the exhaust brake valve to open, the opening adjustment plate rotates away from the adjustment bolt, the valve plate is in the fully open position, thermal management is performed through the intake throttle valve, and step S1 is continued.

[0025] As a further improvement, the thickness of the opening adjustment plate corresponding to the target torque is calibrated according to the exhaust temperature corresponding to the target torque and the actual exhaust temperature, so as to obtain the corresponding rotation angle of the opening adjustment plate and produce the opening adjustment MAP;

[0026] When entering the thermal management working mode, the exhaust temperature corresponding to the target torque and the actual exhaust temperature are calibrated to query the opening adjustment MAP to obtain the corresponding rotation angle, and the operation of the drive mechanism is controlled according to the rotation angle.

[0027] Beneficial Effects

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] The present invention sets an opening adjustment plate on the original adjustment frame, drives the opening adjustment plate to rotate through a driving mechanism to adjust the rotation angle of the limit baffle together with the adjustment bolt, thereby adjusting the opening of the exhaust brake valve. The modification cost is low and the effect is good. It can achieve low-speed and low-load thermal management of the engine and reduce engine emissions. At the same time, it also solves the problem of large intake negative pressure caused by relying entirely on the intake throttle valve for thermal management. The present invention uses a simple mechanical structure to ensure the reliable operation of the system and reduces the failure of electrical components caused by high temperature of the exhaust system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the mechanical exhaust brake valve system of the conventional technology;

[0031] Figure 2 This is a schematic diagram of the exhaust brake valve being fully opened;

[0032] Figure 3 This is a schematic diagram of the exhaust brake valve being fully closed;

[0033] Figure 4 Schematic diagram of adjusting bolts for conventional techniques;

[0034] Figure 5 is a schematic diagram of the system of the present invention;

[0035] Figure 6 It is a left view of the opening adjustment plate in the present invention;

[0036] Figure 7 It is a front view of the opening adjustment plate in the present invention;

[0037] Figure 8 is a schematic diagram of a driving mechanism of the present invention being a motor;

[0038] Fig. 9 It is a schematic diagram of the driving mechanism of the present invention being a cylinder;

[0039] Fig.10It is a schematic diagram of the position where the opening adjustment plate in the present invention is rotated to the position where the valve plate is opened at the adjustment bolt;

[0040] Fig.11 is a cross-sectional schematic diagram of the opening adjustment plate in the present invention;

[0041] Fig.12 It is a flow chart of the control method in the present invention.

[0042] Among them: 1-adjusting frame, 2-adjusting bolt, 3-exhaust brake valve, 4-controller, 5-valve stem, 6-limit baffle, 7-opening adjustment plate, 8-driving mechanism, 9-shift plate, 10-rotating shaft, 11-adsorption rod, 12-reset spring, 13-connecting rod, 14-valve plate. DETAILED DESCRIPTION

[0043] The present invention will be further described below with reference to the specific embodiments in the accompanying drawings.

[0044] See also Figures 5 to 11 A diesel engine thermal management control system includes an adjustment frame 1, an adjustment bolt 2, an exhaust brake valve 3, and a controller 4. The adjustment bolt 2 is fixedly mounted on the adjustment frame 1. The exhaust brake valve 3 is mounted on the exhaust pipe and electrically connected to the controller 4. Specifically, the exhaust brake valve 3 is opened or closed by a cylinder drive, and the cylinder is electrically connected to the controller 4. The valve stem 5 of the exhaust brake valve 3 is provided with a limit baffle 6 corresponding to the position of the adjustment bolt 2. When the limit baffle 6 rotates to the adjustment bolt 2, the valve plate 14 is in a fully open position. An opening adjustment plate 7 is provided between the adjustment bolt 2 and the valve stem 5. The adjustment frame 1 is provided with a driving mechanism 8 for driving the opening adjustment plate 7 to rotate. The driving mechanism 8 is electrically connected to the controller 4. The controller 4 controls the driving mechanism 8 to drive the opening adjustment plate 7 to rotate to the adjustment bolt 2, thereby changing the gap between the valve stem 5 and the adjustment bolt 2, and then changing the maximum rotation angle of the limit baffle 6, so as to achieve the maximum rotation angle of the adjustment valve plate 14. The controller 4 is an ECU.

[0045] The adjustment frame 1 is an L-shaped structure, the adjustment bolt 2 is fixedly mounted on a right angle side of the adjustment frame 1 , and the valve stem 5 of the exhaust brake valve 3 passes through the other right angle side of the adjustment frame 1 .

[0046] The opening adjustment plate 7 is a structure with a small thickness on one side and a large thickness on the other side. For example, the cross section of the opening adjustment plate 7 is a trapezoidal structure. The opening adjustment plate 7 rotates to different positions corresponding to different thicknesses, thereby corresponding to different gaps between the valve stem 5 and the adjusting bolt 2, thereby achieving stepless adjustment of the maximum rotation angle of the valve plate 14. Preferably, the opening adjustment plate 7 is composed of at least two shift plates 9 of different thicknesses connected in sequence, such as Fig.11 As shown, the opening adjustment plate 7 is composed of three shift plates 9 of different thicknesses connected in sequence, which can achieve three different gaps, thereby achieving three levels of adjustment of the rotation angle of the valve plate 14.

[0047] In one embodiment, Figure 8 As shown, the driving mechanism 8 is a motor, and the rotating shaft of the motor is connected to one end of the opening adjustment plate 7.

[0048] In one embodiment, Figure 6 , 7 As shown, the driving mechanism 8 is an electromagnet, one end of the opening adjustment plate 7 is rotatably connected to the adjustment frame 1 through a rotating shaft 10, one end of the rotating shaft 10 is provided with an adsorption rod 11 corresponding to the adsorption end of the electromagnet, and the adsorption rod 11 is provided with a reset spring 12 connected to the adjustment frame 1.

[0049] In one embodiment, Fig. 9 As shown, the driving mechanism 8 is a cylinder or a hydraulic cylinder or an electric push rod. One end of the opening adjustment plate 7 is rotatably connected to the adjustment frame 1 through a rotating shaft 10. A connecting rod 13 is provided at one end of the rotating shaft 10. Both ends of the driving mechanism 8 are rotatably connected to the connecting rod 13 and the adjustment frame 1 respectively.

[0050] See also Fig.12 A diesel engine thermal management control method comprises the following steps:

[0051] Step S1. The controller 4 obtains the engine speed, the throttle opening, the actual exhaust temperature and the exhaust brake request switch signal;

[0052] Step S2. If the exhaust brake request switch is pressed, execute step S3; otherwise, execute step S5;

[0053] Step S3. If the throttle opening is equal to 0, execute step S4; otherwise, execute step S5;

[0054] Step S4. Enter the brake working mode, the controller 4 controls the driving mechanism 8 to reset and the exhaust brake valve 3 to close, the opening adjustment plate 7 rotates away from the adjustment bolt 2, the limit stopper 6 contacts the adjustment bolt 2, and the valve plate 14 is in the fully closed position, such as Figure 3 The position shown in FIG. 1 is continued to execute step S1;

[0055] Step S5. The controller 4 calculates the exhaust temperature corresponding to the target torque according to the engine speed and the throttle opening;

[0056] Step S6. If the exhaust temperature corresponding to the target torque exceeds the first temperature Tmin1 or the actual exhaust temperature far exceeds the first temperature Tmin1, then execute step S9. The actual exhaust temperature far exceeds the first temperature Tmin1, which means that the actual exhaust temperature exceeds the first temperature Tmin1 by more than 100 degrees; otherwise, execute step S7;

[0057] Step S7: If the exhaust temperature corresponding to the target torque is lower than the first temperature Tmin1 and the actual exhaust temperature is lower than the second temperature Tmin2 and the duration t is greater than the set time t dly , then execute step S8, wherein Tmin2>Tmin1, Tmin1 is 250~270℃, Tmin2 is 220~250℃, t dly The time Tmin1 and Tmin2 are used for engine emission control. The temperature is used for post-processing thermal management. Thermal management and DPF regeneration are done well when the action frequency is the lowest. Otherwise, execute step S9.

[0058] Step S8. Enter the thermal management working mode, the controller 4 controls the driving mechanism 8 to work and the exhaust brake valve 3 to close, the opening adjustment plate 7 rotates to the adjusting bolt 2, the limit stopper 6 contacts the opening adjustment plate 7, and the valve plate 14 is in the adjustment position, such as Fig.10 The position shown in FIG. 1 is continued to execute step S1;

[0059] Step S9. Entering the normal working mode, the controller 4 controls the driving mechanism 8 to reset and the exhaust brake valve 3 to open, the opening adjustment plate 7 rotates away from the adjustment bolt 2, and the valve plate 14 is in the fully open position, such as Figure 2 At the position shown, thermal management is performed through the intake throttle valve and step S1 is continued.

[0060] Furthermore, the thickness of the opening adjustment plate 7 corresponding to the target torque can be calibrated in advance according to the exhaust temperature corresponding to the target torque and the actual exhaust temperature, so as to obtain the corresponding rotation angle of the opening adjustment plate 7 and produce the opening adjustment MAP;

[0061] When entering the thermal management working mode, the exhaust temperature corresponding to the target torque and the actual exhaust temperature are calibrated to query the opening adjustment MAP to obtain the corresponding rotation angle, and the drive mechanism 8 is controlled to work according to the rotation angle to perform stepless or multi-stage adjustment of the position of the valve plate 14.

[0062] The above are only preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A diesel engine thermal management control system, comprising an adjustment frame (1), an adjustment bolt (2), an exhaust brake valve (3), and a controller (4), wherein the adjustment bolt (2) is fixedly mounted on the adjustment frame (1), the exhaust brake valve (3) is mounted on an exhaust pipe and electrically connected to the controller (4), and a valve stem (5) of the exhaust brake valve (3) is provided with a limit stopper (6) corresponding to the position of the adjustment bolt (2), characterized in that: An opening adjustment plate (7) is provided between the adjustment bolt (2) and the valve stem (5), and the adjustment frame (1) is provided with a driving mechanism (8) for driving the opening adjustment plate (7) to rotate, and the driving mechanism (8) is electrically connected to the controller (4).

2. A diesel engine thermal management control system according to claim 1, characterized in that: The adjustment frame (1) is an L-shaped structure, the adjustment bolt (2) is fixedly mounted on a right angle side of the adjustment frame (1), and the valve stem (5) of the exhaust brake valve (3) passes through the other right angle side of the adjustment frame (1).

3. A diesel engine thermal management control system according to claim 1, characterized in that: The opening adjustment plate (7) is a structure with a small thickness on one side and a large thickness on the other side.

4. A diesel engine thermal management control system according to claim 3, characterized in that: The opening adjustment plate (7) is composed of at least two shift plates (9) of different thicknesses connected in sequence.

5. A diesel engine thermal management control system according to any one of claims 1 to 4, characterized in that: The driving mechanism (8) is a motor, and the rotating shaft of the motor is connected to one end of the opening adjustment plate (7).

6. A diesel engine thermal management control system according to any one of claims 1 to 4, characterized in that: The driving mechanism (8) is an electromagnet; one end of the opening adjustment plate (7) is rotatably connected to the adjustment frame (1) via a rotating shaft (10); one end of the rotating shaft (10) is provided with an adsorption rod (11) corresponding to the adsorption end of the electromagnet; and the adsorption rod (11) is provided with a return spring (12) connected to the adjustment frame (1).

7. A diesel engine thermal management control system according to any one of claims 1 to 4, characterized in that: The driving mechanism (8) is a pneumatic cylinder or a hydraulic cylinder or an electric push rod; one end of the opening adjustment plate (7) is rotatably connected to the adjustment frame (1) via a rotating shaft (10); one end of the rotating shaft (10) is provided with a connecting rod (13); and both ends of the driving mechanism (8) are rotatably connected to the connecting rod (13) and the adjustment frame (1), respectively.

8. A diesel engine thermal management control system according to claim 1, characterized in that: The controller (4) is an ECU.

9. A control method for a diesel engine thermal management control system according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step S1. The controller (4) obtains the engine speed, the throttle opening, the actual exhaust temperature and the exhaust brake request switch signal; Step S2. If the exhaust brake request switch is pressed, execute step S3; Otherwise, execute step S5; Step S3. If the throttle opening is equal to 0, execute step S4; otherwise, execute step S5; Step S4. Entering the braking working mode, the controller (4) controls the driving mechanism (8) to reset and the exhaust brake valve (3) to close, the opening adjustment plate (7) rotates away from the adjustment bolt (2), the limit stopper (6) contacts the adjustment bolt (2), the valve plate (14) is in the fully closed position, and step S1 is continued; Step S5. The controller (4) calculates the exhaust temperature corresponding to the target torque according to the engine speed and the throttle opening; Step S6. If the exhaust temperature corresponding to the target torque exceeds the first temperature or the actual exhaust temperature exceeds the first temperature by more than 100 degrees, and the first temperature is 250-270°C, then execute step S9; otherwise, execute step S7; Step S7. If the exhaust temperature corresponding to the target torque is lower than the first temperature and the actual exhaust temperature is lower than the second temperature and the duration is longer than the set time, then execute step S8; otherwise, execute step S9; Step S8. Entering the thermal management working mode, the controller (4) controls the driving mechanism (8) to work and the exhaust brake valve (3) to close, the opening adjustment plate (7) rotates to the adjusting bolt (2), the limit stopper (6) contacts the opening adjustment plate (7), the valve plate (14) is located at the adjustment position, and step S1 is continued; Step S9. Entering the normal working mode, the controller (4) controls the driving mechanism (8) to reset and the exhaust brake valve (3) to open, the opening adjustment plate (7) rotates away from the adjustment bolt (2), the valve plate (14) is in the fully open position, and thermal management is performed through the intake throttle valve, and step S1 is continued.

10. The control method of a diesel engine thermal management control system according to claim 9, characterized in that: Calibrate the thickness of the opening adjustment plate (7) corresponding to the target torque according to the exhaust temperature and the actual exhaust temperature, thereby obtaining the corresponding rotation angle of the opening adjustment plate (7), and producing an opening adjustment MAP; When entering the thermal management working mode, the exhaust temperature corresponding to the target torque and the actual exhaust temperature are calibrated to query the opening adjustment MAP to obtain the corresponding rotation angle, and the driving mechanism (8) is controlled to work according to the rotation angle.

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