CN112627947B - Urea pump, anti-blocking control method thereof, SCR device and urea injection system - Google Patents

Abstract

The invention relates to a urea dosing pump and its anti-clogging control method, an SCR device, and a urea injection system. The urea dosing pump comprises a first filtering device, a first pressure difference detection device and a bypass pipeline, and the first filtering device is arranged in the pipeline of the urea dosing pump , the first pressure difference detection device is used to detect the pressure difference between the two ends of the first filter device; the bypass pipeline is connected in parallel with the first filter device, and the bypass pipeline is provided with a control valve; the first pressure difference detection device and the control valve are respectively connected with The controller of the urea dosing pump is connected, and the controller of the urea dosing pump controls the control valve to open when the first differential pressure detection device detects that the pressure difference between the two ends of the first filtering device is greater than the preset value; The bypass pipeline is connected in parallel. When the first filter device is blocked, the system pressure can be built up through the bypass pipeline, so as to avoid the occurrence of the urea dosing pump being mistaken for a faulty part due to the blockage of the first filter device, and reduce unnecessary user needs. loss, improve the reliability of the urea pump, and improve the user experience.

Description

Urea pump and its anti-clogging control method, SCR device, and urea injection system

technical field

The invention relates to the technical field of diesel engine air management systems, in particular to a urea pump and its anti-clogging control method, an SCR device, and a urea injection system.

Background technique

At present, when the urea injection system enters normal operation, if there is a blockage formed by impurities at the filter element of the urea dosing pump and the injection system cannot work normally, the control unit will instruct the urea injection system to work again for many times. After several times of commands, the urea dosing system still cannot work normally, the control unit will send out a fault signal of the urea dosing pump and limit the torque of the whole vehicle. In this case, the urea dosing pump that only needs to replace the filter element will be mistakenly considered to be faulty, which is easy to cause damage to the user. It will cause unnecessary losses and will affect the use of users.

SUMMARY OF THE INVENTION

The first object of the present invention is to provide a urea dosing pump, so as to avoid the situation that the urea dosing pump is mistaken as a faulty part due to the blockage of the filter element, improve the reliability of the urea dosing pump, and improve the user experience.

The second object of the present invention is to provide a urea dosing pump anti-clogging control method, urea injection system and SCR device based on the above urea dosing pump.

To achieve the above object, the present invention provides the following technical solutions:

A urea pump, comprising a first filter device arranged on the pipeline of the urea pump, further comprising:

a first differential pressure detection device for detecting the differential pressure across the first filter device;

a bypass pipeline connected in parallel with the first filter device, the bypass pipeline is provided with a control valve for controlling the on-off of the bypass pipeline;

The first differential pressure detection device and the control valve are respectively connected with the controller of the urea dosing pump, and the controller of the urea dosing pump detects that the two ends of the first filter device are detected by the first differential pressure detection device. When the pressure difference is greater than a preset value, the control valve is controlled to open to conduct the bypass line.

Preferably, an alarm device is also included, the alarm device is connected to the controller of the urea dosing pump, and the controller of the urea dosing pump controls the alarm device to output a blockage fault signal while controlling the opening of the control valve.

Preferably, the control valve is a solenoid valve.

Preferably, at least two bypass pipelines are provided, and each of the bypass pipelines is provided with the control valve respectively.

Preferably, at least one of the bypass lines is provided with a second filter device, and the second filter device is located upstream and/or downstream of the control valve of the bypass line.

Preferably, it also includes a second differential pressure detection device for detecting the pressure difference between the two ends of the bypass pipeline, and the second differential pressure detection device is connected to the vehicle controller.

A urea injection system, comprising the urea pump as described in any one of the above.

An SCR device includes the urea injection system as described above.

A urea dosing pump anti-clogging control method based on any one of the above-mentioned urea pump, comprising the steps:

1) Send a system pressure build-up signal to the urea dosing pump, obtain the pressure value at both ends of the first filter device of the urea dosing pump, and calculate the pressure difference at both ends of the first filter device, if the pressure difference at both ends of the first filter device is less than or equal to a preset value, Then the urea pump executes the system pressure building, and if the pressure difference between the two ends of the first filter device is greater than the preset value, then enter step 2);

2) The control valve that controls the bypass pipeline is opened, and the urea dosing pump executes the system pressure buildup through the bypass pipeline.

Preferably, it also includes the steps:

3) When the control valve of the bypass pipeline is opened, it outputs a blockage fault signal to the user;

4) Obtain the pressure value at both ends of the bypass pipeline, and calculate the pressure difference between the two ends of the bypass pipeline. If the pressure difference between the two ends of the bypass pipeline is less than or equal to the preset value, keep the current state of the urea dosing pump. If the pressure difference between the two ends is greater than the preset value, the urea dosing pump will be controlled to stop, and the vehicle torque will be limited.

It can be seen from the above technical solutions that the present invention discloses a urea dosing pump, which includes a first filtering device, a first differential pressure detection device and a bypass pipeline, wherein the first filtering device is arranged on the side of the urea dosing pump. On the pipeline, it is used to filter the urea pumped by the urea dosing pump, and the first pressure difference detection device is used to detect the pressure difference between the two ends of the first filter device; the bypass pipeline is connected in parallel with the first filter device, and the bypass pipeline is provided with useful The control valve is used to control the on-off of the bypass pipeline; the first differential pressure detection device and the control valve are respectively connected with the controller of the urea dosing pump, and the controller of the urea dosing pump detects the two ends of the first filter device in the first differential pressure detection device. When the pressure difference is greater than the preset value, the control valve is opened to conduct the bypass pipeline; in application, the system pressure build-up signal is first sent to the urea dosing pump. A pressure value at both ends of the filter device, and calculate the pressure difference between the two ends of the first filter device. If the pressure difference between the two ends of the first filter device is less than or equal to the preset value, the first filter device is not blocked, and the urea pump executes the system pressure build-up. If the pressure difference between the two ends of the first filter device is greater than the preset value, it means that the first filter device is blocked, then the control valve that controls the bypass pipeline is opened, and the urea dosing pump executes the system pressure building through the bypass pipeline; Both ends of the first filter device of the above-mentioned urea pump are connected in parallel with bypass pipelines, so that when the first filter device is blocked, the system pressure can be built up through the bypass pipeline, so as to avoid the urea pump being mistakenly caused by the blockage of the first filter device. It is considered that the occurrence of faulty parts can reduce unnecessary losses of users, improve the reliability of the urea dosing pump, and improve the user experience.

The present invention also provides a urea injection system including the above-mentioned urea dosing pump and an SCR device. Since the urea injection system and the SCR device both use the above-mentioned urea dosing pump, the urea injection system and the SCR device have both the beneficial effects of the above-mentioned urea dosing pump. This will not be repeated here.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

Fig. 1 is the partial structure schematic diagram of the urea pump provided in the embodiment of the present invention;

FIG. 2 is a flowchart of a method for preventing clogging of a urea dosing pump according to an embodiment of the present invention.

in:

1 is the first differential pressure detection device; 2 is the first filtering device; 3 is the control valve.

Detailed ways

One of the cores of the present invention is to provide a urea dosing pump, so as to avoid the situation that the urea dosing pump is mistaken as a faulty part due to the blockage of the filter element, improve the reliability of the urea dosing pump, and improve the user experience.

Another core of the present invention is to provide a urea dosing pump anti-clogging control method, urea injection system and SCR device including the above urea dosing pump.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Please refer to FIG. 1. FIG. 1 is a schematic diagram of a partial structure of a urea pump according to an embodiment of the present invention.

The embodiment of the present invention discloses a urea dosing pump, which includes a first filtering device 2, a first differential pressure detection device 1 and a bypass pipeline.

Wherein, the first filter device 2 is arranged on the pipeline of the urea dosing pump to filter the urea pumped by the urea dosing pump, and the first pressure difference detection device 1 is used to detect the pressure difference between the two ends of the first filter device 2; the bypass pipe The pipeline is connected in parallel with the first filter device 2, one or more bypass pipelines can be set, and the bypass pipeline is provided with a control valve 3 for controlling the on-off of the bypass pipeline; the first pressure difference detection device 1 and the control valve 3 They are respectively connected with the controller of the urea dosing pump, and the controller of the urea dosing pump controls the control valve 3 to open when the first pressure difference detection device 1 detects that the pressure difference between the two ends of the first filter device 2 is greater than the preset value to conduct the bypass pipeline. .

It can be seen that, compared with the prior art, when the urea dosing pump provided by the embodiment of the present invention is applied, it first sends a system pressure building signal to the urea dosing pump. A pressure value at both ends of the filter device 2, and calculate the pressure difference between the two ends of the first filter device 2. If the pressure difference between the two ends of the first filter device 2 is less than or equal to the preset value, the first filter device 2 is not blocked, and the urea pump executes the system Build the pressure, if the pressure difference between the two ends of the first filter device 2 is greater than the preset value, it means that the first filter device 2 is blocked, then the control valve 3 that controls the bypass line is opened, and the urea pump executes the system pressure build-up through the bypass line. It can be seen that, by connecting the bypass pipelines in parallel at both ends of the first filter device 2 of the above-mentioned urea dosing pump, when the first filter device 2 is blocked, the system pressure can be built through the bypass pipeline, thereby avoiding the The urea dosing pump is mistaken for a faulty part caused by the blockage of the filter device, which reduces unnecessary losses of users, improves the reliability of the urea dosing pump, and improves the user experience.

As preferably, the above-mentioned urea dosing pump also includes an alarm device, the alarm device is connected with the controller of the urea dosing pump, and the controller of the urea dosing pump controls the alarm device to output a blockage fault signal when the control valve 3 is opened, to remind the user to stop the urea dosing Cleaning and replacement of the first filter device 2 of the pump.

Preferably, the above-mentioned control valve 3 is a solenoid valve.

In a preferred embodiment of the present invention, there are at least two bypass pipelines, and each bypass pipeline is provided with a control valve 3 respectively, and each bypass can be realized by controlling the control valve 3 on each bypass pipeline When the pipeline is turned on or off, when the control valve 3 of one of the bypass pipelines fails or is blocked, the other bypass pipelines can be used to ensure the normal progress of the system pressure buildup, thereby improving the reliability of the urea dosing pump.

Further, at least one bypass pipeline is provided with a second filter device, the second filter device is located upstream and/or downstream of the control valve 3 of the bypass pipeline, and the second filter device is used for convection through the bypass pipeline. The urea is filtered to reduce the probability of the urea nozzle being blocked.

Preferably, it also includes a second differential pressure detection device for detecting the pressure difference at both ends of the bypass pipeline, the second differential pressure detection device is connected to the vehicle controller, and the bypass pipeline is detected in the second differential pressure detection device When the pressure difference between the two ends of the road is greater than the preset value, the urea dosing pump is controlled to stop to protect the urea dosing pump, and the vehicle torque is limited.

Embodiments of the present invention also provide a urea injection system and an SCR device including the above-mentioned urea dosing pump. Since the above-mentioned urea dosing pump has the above-mentioned technical effects, please refer to the above-mentioned embodiments for the technical effects of the urea-injection system and the SCR device including the urea-dosing pump. .

Further, an embodiment of the present invention also provides a urea dosing pump anti-blocking control method based on the urea dosing pump described in the above embodiment, as shown in FIG. 2 , the control method includes the steps:

1) Send the system pressure building signal to the urea dosing pump, obtain the pressure value at both ends of the first filter device 2 of the urea dosing pump, and calculate the pressure difference between the two ends of the first filter device 2, if the pressure difference between the two ends of the first filter device 2 is less than or equal to the preset value. Set the value, then the urea dosing pump executes the system pressure building, if the pressure difference between the two ends of the first filter device 2 is greater than the preset value, then enter step 2);

After obtaining the system decompression signal, first control the urea dosing pump to start while obtaining the pressure difference across the first filter device 2 of the urea pump, if the pressure difference across the first filter device 2 is less than or equal to the preset value, then the urea pump keeps moving , and the system pressure builds up. If the pressure difference between the two ends of the first filter device 2 is greater than the preset value, it means that the first filter device 2 has been blocked.

2) The control valve 3 that controls the bypass pipeline is opened, and the urea dosing pump executes the system pressure buildup through the bypass pipeline;

When the first filter device 2 is blocked, the system pressure cannot be built only by relying on the pipeline where the first filter device 2 is installed. At this time, the control valve 3 on the bypass pipeline needs to be opened, and the system can be realized by using the bypass pipeline. Build pressure.

Preferably, the above-mentioned control method further comprises the steps:

3) When the control valve 3 of the control bypass pipeline is opened, the blockage fault signal is output to the user;

To remind the user to clean and replace the first filter device 2 of the urea dosing pump after parking.

4) Obtain the pressure value at both ends of the bypass pipeline, and calculate the pressure difference between the two ends of the bypass pipeline. If the pressure difference between the two ends of the bypass pipeline is less than or equal to the preset value, keep the current state of the urea dosing pump. If the pressure difference between the two ends is greater than the preset value, the urea dosing pump will be controlled to stop, and the vehicle torque will be limited;

If the pressure difference between the two ends of the bypass pipeline is also greater than the preset value, it means that the control valve 3 of the bypass pipeline fails to open in time or the control valve 3 and the second filter device are blocked, and the system pressure cannot be built at this time. The urea dosing pump should be stopped to protect the urea dosing pump and limit the torque of the whole vehicle.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other.

The above description of the disclosed embodiments enables any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. a urea pump, comprising the first filter device that is arranged on the pipeline of the urea pump, is characterized in that, also comprises: a first differential pressure detection device for detecting the differential pressure across the first filter device; a bypass pipeline connected in parallel with the first filter device, the bypass pipeline is provided with a control valve for controlling the on-off of the bypass pipeline; The first differential pressure detection device and the control valve are respectively connected with the controller of the urea dosing pump, and the controller of the urea dosing pump detects that the two ends of the first filter device are detected by the first differential pressure detection device. When the pressure difference is greater than a preset value, the control valve is controlled to open to conduct the bypass pipeline; It also includes a second differential pressure detection device for detecting the pressure difference between the two ends of the bypass pipeline, and the second differential pressure detection device is connected to the vehicle controller. 2. The urea dosing pump according to claim 1, further comprising an alarm device, the alarm device is connected with the controller of the urea dosing pump, and the controller of the urea dosing pump controls the opening of the control valve when the control valve is opened. At the same time, the alarm device is controlled to output a blockage fault signal. 3. The urea pump according to claim 1 or 2, wherein the control valve is a solenoid valve. 4 . The urea pump according to claim 1 or 2 , wherein at least two bypass pipelines are provided, and the control valve is respectively provided on each of the bypass pipelines. 5 . 5. The urea dosing pump according to claim 4, characterized in that, at least one of the bypass pipelines is provided with a second filter device, and the second filter device is located upstream and/or upstream of the control valve of the bypass pipeline. or downstream. 6. A urea injection system, characterized in that it comprises the urea pump according to any one of claims 1-5. 7. An SCR device, characterized by comprising the urea injection system as claimed in claim 6. 8. a urea pump anti-clogging control method based on the urea pump described in any one of claims 1-5, is characterized in that, comprises the steps: 1) Send a system pressure build-up signal to the urea dosing pump, obtain the pressure value at both ends of the first filter device of the urea dosing pump, and calculate the pressure difference at both ends of the first filter device, if the pressure difference at both ends of the first filter device is less than or equal to a preset value, Then the urea pump executes the system pressure building, and if the pressure difference between the two ends of the first filter device is greater than the preset value, then enter step 2); 2) The control valve that controls the bypass pipeline is opened, and the urea dosing pump executes the system pressure buildup through the bypass pipeline; 3) When the control valve of the bypass pipeline is opened, it outputs a blockage fault signal to the user; 4) Obtain the pressure value at both ends of the bypass pipeline, and calculate the pressure difference between the two ends of the bypass pipeline. If the pressure difference between the two ends of the bypass pipeline is less than or equal to the preset value, keep the current state of the urea dosing pump. If the pressure difference between the two ends is greater than the preset value, the urea dosing pump will be controlled to stop, and the vehicle torque will be limited.

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