WO2012122756A1

WO2012122756A1 - After-treatment regeneration control method and device for construction machinery

Info

Publication number: WO2012122756A1
Application number: PCT/CN2011/076252
Authority: WO
Inventors: 曹东辉; 舒全禄; 石向星; 孙军
Original assignee: 湖南三一智能控制设备有限公司; 三一重机有限公司
Priority date: 2011-03-17
Filing date: 2011-06-24
Publication date: 2012-09-20
Also published as: CN102146832A

Abstract

Disclosed is an after-treatment regeneration control method for a construction machinery. When the construction machinery is in a low load or idle state and the exhaust temperature of an engine(1) is lower than an automatic regeneration temperature, an engine controller sends a signal to a main controller. The overflow pressure of an electromagnetic proportional overflow valve (6) is increased by the main controller to increase the load on the PTO port (4) of the engine (1), and the exhaust temperature of the engine (1) is raised to realize regeneration. Also disclosed is an after-treatment regeneration control device for the construction machinery, including a load pump (5) and the electromagnetic proportional overflow valve (6) connected with the output port of the load pump (5). The input port of the load pump (5) is connected with the PTO port (4) of the engine (1) and the control end of the electromagnetic proportional overflow valve (6) is connected to the main controller. The oil returning ports of the the load pump (5) and the electromagnetic proportional overflow valve (6) are respectively connected to an oil tank. The loading is independent from the hydraulic system, so the regeneration can be realized without stopping the construction machinery from working, and thus a work efficiency is improved.

Description

Engineering machinery post-processing regeneration control method and device

[0001] The present invention relates to a power control method, and in particular to a construction machine post-processing regeneration control method and apparatus.

5 Background

[0002] At present, in the fields of construction, water conservancy and other engineering, various types of construction machinery are widely used, such as excavators, cranes, bulldozers, etc. These construction machines for engineering construction are collectively referred to as construction machinery. The construction machinery mainly consists of a traveling device, a slewing device, a cab, a working device and a power device. The power device is generally a diesel engine engine. The diesel engine is an internal combustion engine that uses diesel as a fuel. After burning the fuel, the piston in the cylinder is pushed back and forth. Motion ⁰ converts the chemical energy in the fuel into mechanical energy that drives the vehicle's action. It has the advantages of high thermal efficiency, relatively high power and saving diesel fuel, and thus is widely used in the power plant of construction machinery.

[0003] In actual use of construction machinery, its diesel engine will inevitably emit a large amount of exhaust gas, and particulate matter (PM) in the exhaust gas will cause greater environmental pollution. As people's awareness of environmental protection increases gradually, Controlling the emission of particulate matter from the exhaust gas of diesel engines in excavators is an important problem to be overcome. Therefore, it is essential to eliminate particulate matter emissions from diesel engines by exhaust gas aftertreatment mode ⁵ . The provision of a particulate filter (DPF) at the exhaust end of the engine is one of the more effective means of controlling the particulate matter of diesel engine exhaust. The particulate filter is mainly to physically capture the particles carried in the exhaust gas emitted by the diesel engine. After the time, the regeneration process is carried out to clean the trapped particulate matter to reduce its impact on the performance of the diesel engine.

[0004] Although DPF can effectively control the particles in the exhaust gas, there are certain deficiencies, that is, work.

: ° When the machine is working at idle speed and low load, the load is not very large, the engine exhaust temperature is low, the DPF can't self-clean and regenerate, and it needs to be cleaned up. This requires additional load. The current load is increased by adding to the hydraulic system circuit. Electromagnetic switching valve or throttle valve is realized, and the construction machinery must stop working, because the regenerative load interferes with the normal working hydraulic load, affecting the normal operation of the machine, and increasing the above-mentioned valve will increase the energy consumption of the entire hydraulic system. There is also a way to connect a gear pump from the main pump PTO port, and then connect a proportional relief valve to form an independent hydraulic aid.

^{: 5} assisted loading system, but this method also has drawbacks. When the machine is in the light load regeneration process, the driver performs heavy load operation. This is that the absorbed power of the main pump will be greater than the output power of the engine, which will cause the main pump and the engine. The coupled coupling wears and reduces its service life.

Summary of the invention

[0005] An object of the present invention is to provide a construction machinery post-processing regeneration control method and apparatus, using the method, so that The load and the hydraulic system are independent of each other, and regeneration is not required to stop the work of the construction machinery, which improves the work efficiency.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: A construction machinery post-processing regeneration control method, when the construction machinery is in a light load or idle state, the exhaust temperature of the engine is lower than the automatic regeneration temperature. The engine controller sends a signal to the main controller to increase the relief pressure of the electromagnetic proportional relief valve, increase the engine PTO port load, increase the engine exhaust temperature, and achieve regeneration.

[0007] An engineering machinery post-processing regeneration control device includes a loading pump and an electromagnetic proportional relief valve connected to the loading pump output port, the input port of the loading pump is connected to a PTO of the engineering machinery engine, and the electromagnetic ratio The control end of the relief valve is connected to the engineering machinery main controller, and the oil return ports of the loading pump and the electromagnetic proportional relief valve are respectively connected to the oil tank.

[0008] In the above technical solution, the construction machinery is currently widely used, and both adopt a diesel engine, and a particulate filter (DPF) is installed at the exhaust end of the engine to filter out particles emitted by the engine, and the particulate filter The control software is installed in the electronic control module of the engine controller. The inside of the particulate filter is provided with a sensor, an inlet temperature sensor arranged before the oxidation catalytic converter (DOC), an outlet temperature sensor after the oxidation catalytic converter (DOC), and a pressure sensor before and after the DPF filter. These sensors will The DPF temperature and pressure status information feedback is transmitted to the engine controller, and the engine controller detects the particulate filter inlet and outlet temperature and pressure difference to determine the working state of the particulate filter, and simultaneously detects the particulate filter control switch, and the engine controller will The particulate filter and control switch information is transmitted to the main controller via the CAN bus. The main controller adjusts the construction machinery according to the state of the particulate filter. When the engine is under light load or idle state, its exhaust temperature is lower than the regeneration temperature, the loading pump is installed at the PTO port of the engine, and the electromagnetic proportional relief valve is added to the output port of the loading pump to form an independent hydraulic load loading system. The main controller adjusts the overflow pressure of the electromagnetic proportional relief valve to control the load, thereby improving the engine exhaust temperature and realizing regeneration. Under light load conditions, the load needs to be small, and in the idle state, the load needs to be large. The specific loading load is determined according to the on-site commissioning of the construction machinery.

[0009] Due to the above technical solutions, the present invention has the following advantages over the prior art:

1. The invention connects the electromagnetic proportional relief valve to the loading pump output port by loading the pump in the PTO connection of the engine, and adjusting the overflow pressure of the electromagnetic proportional relief valve through the main controller when the engineering machine is in an idle or light load state. , increase the engine load, thereby increasing the engine exhaust temperature to achieve regeneration, so that the construction machinery does not need to stop the operation when regenerating, improving the working efficiency;

2. The present invention is independent of the loading load on the PTO port of the engine, and the loading load system and the engineering machinery hydraulic load system are independent of each other, and do not affect each other, and there is no need to make large-scale changes to the existing hydraulic system;

3. The invention has simple structure, convenient operation, and is easy to implement, and is suitable for popularization and use.

DRAWINGS 1 is a schematic structural diagram of a DPF according to Embodiment 1 of the present invention;

2 is a schematic block diagram of Embodiment 1 of the present invention;

3 is a schematic structural view of a hydraulic system according to Embodiment 1 of the present invention;

4 is a schematic flow chart of Embodiment 1 of the present invention;

FIG. 5 is a schematic structural diagram of a regeneration control apparatus according to Embodiment 1 of the present invention.

[0011] wherein: 1, the engine; 2, hydraulic main pump; 3, pilot pump; 4, the main pump PTO port; 5, loading the pump; 6, electromagnetic proportional relief valve; 7, safety valve; 8, 9, 10 , remote control valve; 12, 14, 15, flow control valve; 13, hydraulic motor; 16, 17, hydraulic cylinder.

detailed description

[0012] The present invention is further described below in conjunction with the accompanying drawings and embodiments:

Embodiment 1: Referring to Figures 1 to 5, an engineering machinery post-processing regeneration control method, when the construction machine is in a light load or idle state, the exhaust temperature of the engine is lower than the automatic regeneration temperature, and the engine controller The main controller sends a signal to increase the relief pressure of the electromagnetic proportional relief valve, increase the engine PTO port load, increase the engine exhaust temperature, and achieve regeneration.

[0013] An engineering machinery post-processing regeneration control device includes a loading pump and an electromagnetic proportional relief valve connected to the loading pump output port, the input port of the loading pump is connected with the PTO of the engineering machinery engine, and the electromagnetic ratio The control end of the relief valve is connected to the engineering machinery main controller, and the oil return ports of the loading pump and the electromagnetic proportional relief valve are respectively connected to the oil tank.

[0014] Referring to FIG. 1, when the engine exhaust gas enters from the inlet of the DPF, the NO in the exhaust gas is oxidized to N02 by using a catalyst in an oxidation catalytic converter (DOC), and then N02 is used in the DPF to capture oxygen. The collected PM (PM refers to the particle, Particulate Matter), in order to make the above process work normally, the temperature before the DOC must reach 250 °C or higher, the temperature in the T1 is detected by the engine controller, and the temperature before the DPF must be reached. Above 500 °C, it can be fully regenerated. The temperature in T2 is detected by the engine controller. The differential pressure sensor P1 is installed at the front and rear of the DPF. The engine controller determines the degree of clogging of the DPF by detecting the value of PI, and issues the regeneration request.

[0015] Referring to FIG. 2, the engine controller detects the temperature and pressure signals in the DPF device. When the machine is under light load operation or idle state, the T1 temperature is lower than 250 ° C, and the catalyst in the DOC cannot react normally, which cannot be realized. The regeneration of the DPF requires an additional load. At this time, the engine controller sends a "regeneration auxiliary signal" to the main controller, asking the main controller to increase the load, and simultaneously sending a regeneration icon to the display for display, and the driver to the DPF regeneration switch. Take the appropriate action. After receiving the signal, the main controller outputs a PWM (Pulse-Width Modulation) signal to adjust the relief pressure of the electromagnetic proportional relief valve to a target value, so that the engine PTO port increases the required load and increases the exhaust. Temperature, to achieve DPF regeneration, when the regeneration is over, the engine controller sends an end signal to the main controller, the main control The relief pressure of the relief valve is reduced to zero and the load is stopped.

[0016] As shown in FIG. 3, a hydraulic main circuit system and a hydraulic auxiliary load circuit system mounted on the construction machine of the present embodiment are shown. The hydraulic main circuit device of the construction machine includes: a variable capacity hydraulic pressure driven by the engine 1. The main pump 2 and the pilot pump 3 of a constant capacity, the pilot pump 3 is connected with the safety valve 7, and the 8, 9, 10 remote control valve controls the opening of the flow control valve according to the displacement of the handle, and the hydraulic main pump 2 The discharged pressure oil drives a plurality of actuators such as the hydraulic motor 13, the hydraulic cylinders 16, 17 to operate. The loading load circuit is composed of the engine 1, the main pump PTO port 4, the loading pump 5 is installed on the PTO port 4 of the engine, and the electromagnetic proportional relief valve 6 is installed on the pipeline of the loading pump 5, when the main controller receives the "loading signal" After that, the PWM signal is output, and the relief pressure of the electromagnetic proportional relief valve 6 is adjusted to achieve hydraulic loading.

[0017] The specific loading process is shown in FIG. 4, the main controller detects whether the loading signal is, if any, adjusts the overflow pressure of the PTO loading pump to a target value, and increases the required hydraulic load; if not, adjusts the PTO loading. The pump has an overflow pressure of 0 and does not load. In order to prevent the engine from entering the heavy-duty operation mode in the light-load operation mode, the main controller detects the engine output power. If the engine output power is less than 70% of the total power, continue to detect the load signal. If not, disconnect the PTO. The port electromagnetic proportional relief valve, end loading, if any, continue to load; if the engine output power is higher than 70%, directly load the electromagnetic proportional relief valve current to end loading.

Claims

Claim

A method for post-processing regeneration control of an engineering machine, characterized in that: when the construction machine is in a light load or idle state, the exhaust temperature of the engine is lower than the automatic regeneration temperature, and the engine controller sends a signal to the main controller. Increase the overflow pressure of the electromagnetic proportional relief valve, increase the engine PTO port load, increase the engine exhaust temperature, and achieve regeneration.

2. An engineering machinery post-processing regeneration control device, comprising: a loading pump (5) and an electromagnetic proportional relief valve (6) connected to the loading pump output port, the input port of the loading pump and the construction machine The PTO connection of the engine, the control end of the electromagnetic proportional relief valve is connected to the engineering machinery main controller, and the oil return ports of the loading pump and the electromagnetic proportional relief valve are respectively connected to the oil tank.