CN109386352B - Supply module for exhaust gas aftertreatment and exhaust gas aftertreatment device - Google Patents
Supply module for exhaust gas aftertreatment and exhaust gas aftertreatment device Download PDFInfo
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- CN109386352B CN109386352B CN201710675298.XA CN201710675298A CN109386352B CN 109386352 B CN109386352 B CN 109386352B CN 201710675298 A CN201710675298 A CN 201710675298A CN 109386352 B CN109386352 B CN 109386352B
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- supply module
- delivery valve
- exhaust aftertreatment
- valve
- line
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- 239000003795 chemical substances by application Substances 0.000 claims description 40
- 238000002347 injection Methods 0.000 claims description 21
- 239000007924 injection Substances 0.000 claims description 21
- 239000012528 membrane Substances 0.000 claims description 16
- 230000005484 gravity Effects 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 47
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 10
- 239000004202 carbamide Substances 0.000 description 10
- 239000000243 solution Substances 0.000 description 9
- 230000007423 decrease Effects 0.000 description 7
- 239000007864 aqueous solution Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 230000008602 contraction Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010926 purge Methods 0.000 description 2
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000010531 catalytic reduction reaction Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- WTHDKMILWLGDKL-UHFFFAOYSA-N urea;hydrate Chemical compound O.NC(N)=O WTHDKMILWLGDKL-UHFFFAOYSA-N 0.000 description 1
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
- F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2610/00—Adding substances to exhaust gases
- F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2610/00—Adding substances to exhaust gases
- F01N2610/14—Arrangements for the supply of substances, e.g. conduits
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2610/00—Adding substances to exhaust gases
- F01N2610/14—Arrangements for the supply of substances, e.g. conduits
- F01N2610/1406—Storage means for substances, e.g. tanks or reservoirs
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2610/00—Adding substances to exhaust gases
- F01N2610/14—Arrangements for the supply of substances, e.g. conduits
- F01N2610/1433—Pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2610/00—Adding substances to exhaust gases
- F01N2610/14—Arrangements for the supply of substances, e.g. conduits
- F01N2610/1453—Sprayers or atomisers; Arrangement thereof in the exhaust apparatus
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
The application relates to a supply module for exhaust gas aftertreatment, comprising: a pump configured to deliver an exhaust aftertreatment between the suction line and the pressure line; a reversing valve configured to switch between a normal operating phase in which the exhaust aftertreatment agent flows from the suction line to the pressure line and an evacuation phase in which the exhaust aftertreatment agent flows from the pressure line to the suction line; a delivery valve for passing the exhaust aftertreatment agent sucked into or discharged from the pump in one direction; wherein the delivery valve is configured to open at an opening pressure that is derived based on a temperature change experienced by the supply module after an evacuation phase. The application also relates to an exhaust gas aftertreatment device comprising the supply module. According to the application, the risk of damage to the supply module can be eliminated, and the structure is simple and reliable.
Description
Technical Field
The application relates to the field of exhaust aftertreatment of engines, in particular to a supply module for exhaust aftertreatment and an exhaust aftertreatment device comprising the supply module.
Background
In order to reduce the pollution of the engine tail gas to the air, a tail gas post-treatment device is widely adopted to further treat the tail gas. The existing exhaust gas post-treatment device generally conveys an exhaust gas post-treatment agent (for example, urea aqueous solution) to an injection module through a supply module when the system detects that the exhaust gas exceeds the standard, and then the injection module injects the exhaust gas post-treatment agent to an exhaust pipe to enable the exhaust gas post-treatment agent and the exhaust gas to undergo catalytic reduction reaction in the exhaust pipe, so that the content of harmful gases in the exhaust gas is reduced. For this purpose, the exhaust gas treatment device generally comprises an exhaust gas aftertreatment agent tank, a suction line, a supply module, a pressure line and an injection module. The supply module sucks the exhaust gas treatment agent out of the storage tank through the suction pipeline and conveys the exhaust gas treatment agent to the injection module through the pressure pipeline. In addition, a return line from the supply module to the tank is typically provided in order to regulate the pressure in the pressure line and return excess exhaust aftertreatment agent to the tank. In this way, fluid exiting the supply module flows one way to the pressure line and the other way to the return line.
The common exhaust gas aftertreatment agent is an aqueous urea solution, however, the aqueous urea solution becomes ice at low temperature and expands in volume, which is liable to damage the exhaust gas aftertreatment device. Therefore, when it is necessary to shut down the engine, it is necessary to control the supply module to operate in reverse so as to withdraw the residual urea aqueous solution in the pressure line from the injection module, the pressure line and the supply module back to the tank. However, when the entire system is shut down, the internal piping will be isolated from the external environment without air exchange. As the internal and external temperatures decrease, the internal pressure of the system will decrease compared to the external atmospheric pressure, creating a negative pressure. This negative pressure will cause the urea-water solution to be refilled into the supply module via the suction line. Therefore, in a low-temperature environment, this phenomenon may damage the supply module or the like.
To solve this problem, two schemes are currently disclosed. One solution is to remove the one-way valve in the return line so that the pressure in the system is always balanced with the external pressure. Thus, even in a low-temperature environment, it is desirable that the refilling phenomenon does not occur. However, the drawbacks of this approach are: when the length of the return line is short compared to the pressure line, it is not sufficient to completely empty the pressure line. Another solution is to add a valve in the suction line for opening or closing the suction line. When the engine is shut down, the valve is also closed to prevent refilling of the supply module. However, the drawbacks of this approach are: when the control is electrically operated, the control system is more complex; when controlled manually, the user easily forgets to close the valve and there is still a risk of damaging the supply module.
Thus, there is a need for a simple, reliable supply module and exhaust aftertreatment device.
Disclosure of Invention
The object of the present application is to overcome at least one of the problems of the existing exhaust gas aftertreatment devices, and to propose an improved supply module and an exhaust gas aftertreatment device comprising such a supply module, whereby the risk of damaging the supply module is eliminated in a simple and reliable manner.
To this end, according to an aspect of the present application, there is provided a supply module for exhaust gas aftertreatment, the supply module comprising:
a pump configured to deliver an exhaust aftertreatment between the suction line and the pressure line;
A reversing valve configured to switch between a normal operating phase in which the exhaust aftertreatment agent flows from the suction line to the pressure line and an evacuation phase in which the exhaust aftertreatment agent flows from the pressure line to the suction line;
A delivery valve for passing the exhaust aftertreatment agent sucked into or discharged from the pump in one direction;
Wherein the delivery valve is configured to open at an opening pressure that is derived based on a temperature change experienced by the supply module after an evacuation phase.
According to another aspect of the present application, there is provided an exhaust gas aftertreatment device comprising:
a storage tank for storing an exhaust aftertreatment;
the injection module is used for injecting the exhaust gas aftertreatment agent;
A supply module as described above for supplying the exhaust aftertreatment agent from the reservoir to the injection module;
A suction line connected between the tank and the supply module; and
A pressure line connected between the supply module and the injection module.
Compared with the prior art, the application sets the opening pressure at the delivery valve in the supply module, so that the delivery valve can be opened only under a certain pressure. Thus, after the evacuation phase, when the air in the closed volume formed by the pipe or component downstream of the delivery valve during the normal operation phase contracts with a decrease in temperature, the exhaust aftertreatment agent is not caused to enter the supply module along the suction pipe if the pressure created by the contraction of the air is insufficient to open the delivery valve. Thus, the risk of damage to the feed module is eliminated. The application has simple structure and does not need to change the structure of the existing supply module greatly.
Drawings
The present application will be further explained below with reference to the drawings in which exemplary embodiments of the present application are described in detail. In the drawings:
FIG. 1 is a functional block diagram of an exhaust aftertreatment device according to an embodiment of the present disclosure;
fig. 2 is a schematic partial cross-sectional view of an example of the supply module shown in fig. 1.
Detailed Description
Preferred embodiments of the present application are described in detail below with reference to examples. In a preferred embodiment of the application, the application is described taking the example of a feed module comprising a diaphragm pump. Those skilled in the art will appreciate that these exemplary embodiments are not meant to be limiting in any way. Furthermore, embodiments of the application and features of the embodiments may be combined with each other without conflict. In the drawings, other components are omitted for brevity, but this does not indicate that the supply module and exhaust aftertreatment device of the application may not include other components.
FIG. 1 is a functional block diagram of an exhaust aftertreatment device, according to an embodiment of the present disclosure. As shown in fig. 1, other components of the exhaust aftertreatment device of the application are all conventional, except for the supply module 20. The exhaust aftertreatment device comprises a tank 10 for storing an exhaust aftertreatment agent, an injection module 40 for injecting the exhaust aftertreatment agent, a supply module 20 for delivering the exhaust aftertreatment agent from the tank 10 to the injection module 40. Accordingly, the exhaust gas aftertreatment device further comprises a suction line 70 and a pressure line 30, wherein the suction line 70 is connected between the tank 10 and the supply module 20, and the pressure line 30 is connected between the supply module 20 and the injection module 40.
In addition, in the embodiment shown in FIG. 1, the exhaust aftertreatment device also includes a return line 60. A return line 60 is coupled between the supply module 20 and the tank 10, and is capable of returning the exhaust aftertreatment agent discharged from the supply module 20 to the tank 10. In the return line 60, there is also a return connection 50, which includes a throttle valve and a one-way valve, to control the pressure stabilization within the system.
The supply module 20 is further described below with reference to fig. 1. As shown in the dotted line portion of fig. 1, the supply module 20 includes a pump 23, a reverse valve 21, a suction valve 22, and a delivery valve 24. Pump 23 is configured to deliver an exhaust aftertreatment between suction line 70 and pressure line 30. The reversing valve 21 is configured to switch between a normal operation phase in which the exhaust aftertreatment agent flows from the suction line 70 to the pressure line 30 and an evacuation phase in which the exhaust aftertreatment agent flows from the pressure line 30 to the suction line 70. In one embodiment, the reversing valve 21 includes a spring force position and an electromagnetic force position. When the reversing valve 21 is in the spring force position, the exhaust aftertreatment agent can be caused to flow from the suction line 70 into the pump 23 and out of the pump 23 into the pressure line 30, thereby achieving normal exhaust aftertreatment operation, i.e., a normal run phase. When the reversing valve 21 is in the electromagnetic force position, i.e., the evacuation phase, the exhaust aftertreatment agent is allowed to flow from the pressure line 30 into the pump 23 and out of the pump 23 into the suction line 70, thereby effecting the evacuation operation of the exhaust aftertreatment device. Because the reversing valve 21 is a common component in existing supply modules, it will not be described in further detail herein. Both the suction valve 22 and the delivery valve 24 are check valves for passing the exhaust aftertreatment agent either into the pump 22 or out of the pump 22 in one direction. In addition, to filter the exhaust aftertreatment agent prior to entering injection module 40, supply module 20 typically also includes a filter (not shown) downstream of delivery valve 24 during normal operation. The filter is in communication with a pressure line 30. As described above, the components and lines downstream of the transfer valve 24 during the normal operation phase include the pressure line 30 and the filter of the supply module 20. In addition, in another embodiment that includes a return line, the line downstream of the transfer valve 24 during the normal operation phase also includes a return line 60. Of course, other components or lines downstream of the transfer valve 24 during normal operation may also be provided, depending on the application.
The above-described structure is substantially the same as that of the conventional supply module. For the sake of simplicity of description, only the pressure line 30 and the filter of the supply module 20 are represented hereinafter as lines and components downstream of the delivery valve 24 during the normal operating phase, wherein the return line 60 and other lines and/or components are not included. However, the principles described herein are equally applicable to other embodiments including return line 60 and other lines and/or components.
Typically, in a conventional supply module (described with reference to fig. 1, but with the delivery valve 24 being different), during system shut-down, i.e., after the drain phase, the injection valve in the injection module 40 is closed and the delivery valve 24 is closed, such that a closed volume is formed within the pressure line 30 and the filter of the supply module 20. When the air in the pressure line 30 and the filter of the supply module 20 contracts as the temperature decreases, a negative pressure occurs in the pressure line 30 and the supply module 20, thereby creating a pressure difference between the pressure line 30 and the tank 10, causing the suction valve 22 and the delivery valve 24 to open. This may result in the exhaust gas aftertreatment agent refilling the supply module 20 via the suction line 70. If the suction line 70 is too short, the refilled exhaust aftertreatment agent will fill the suction line 70 and enter the supply module 20, e.g., in the region of the reversing valve 21. As the ambient temperature decreases, the exhaust aftertreatment agent will expand due to icing when the temperature of the exhaust aftertreatment agent is below its freezing point temperature, thereby damaging the supply module 20. In a typical vehicle exhaust aftertreatment system circuit arrangement, the pressure line 30 will typically be much longer than the suction line 70 and the filter volume of the supply module 20 will be large, so the sum of the volume within the pressure line 30 and the filter volume of the supply module 20 will be much greater than the volume of the suction line 70. The negative pressure generated in the pressure line 30 and in the filter of the supply module 20 is a major influencing factor for the occurrence of refilling. Of course, in the case where the suction line 70 is long in the partial vehicle exhaust aftertreatment system line arrangement, even if the refilling phenomenon occurs at this time, the refilled exhaust aftertreatment agent simply stays in the suction line 70 and does not fill the supply module 20. Therefore, if only the contraction of air in the suction duct 70 is considered, the phenomenon of refilling the supply module does not occur regardless of the length.
It is noted that the supply module of the present application differs in the structure of the delivery valve 24. The delivery valve 24 is configured to open at an opening pressure p. That is, the delivery valve 24 is set to be opened when receiving a pressure exceeding the opening pressure p. In this way, even if the air in the pressure line 30 and the filter of the supply module 20 is contracted in the low temperature environment, the generated negative pressure is insufficient to open the delivery valve 24, thereby separating the pressure line 30 and the filter of the supply module 20 from the suction line 70. This avoids the problem of the exhaust gas aftertreatment being refilled into the supply module 20 under the influence of the negative pressure in the pressure line 30 and the filter of the supply module 20.
In order to achieve a good separation of the pressure line 30 from the filter and suction line 70 of the supply module 20, the opening pressure p of the delivery valve 24 must be calculated with a strict calculation. As described above, after the evacuation phase, a closed volume is formed inside the pressure line 30 and the filter of the supply module 20, the air inside which contracts with the temperature variation to which the supply module 20 is subjected, and the negative pressure thus generated is a main factor in the occurrence of the refilling phenomenon. The volume of the air in the pressure line 30 and the filter of the supply module 20 is fixed without refilling. The opening pressure p of the delivery valve 24 in the supply module 20 of the present application is thus derived based on the temperature variation to which the supply module 20 is subjected after the evacuation phase.
An exemplary method for deriving the opening pressure p of the delivery valve 24 by calculation is given below. It is well known that for a quantity of gas, its temperature and pressure can be calculated using the existing ideal gas state equation (or Charles' law):
P*V＝n*R*T
Wherein: p is the pressure of the gas, V is the volume of the gas, n is the amount of substance of the gas, R is a constant (r= 8.314), and T is the temperature of the gas.
After performing the purging operation (i.e., the purging phase), the pressure line 30 and the filter of the supply module 20 are charged with gas at an external atmospheric pressure P (e.g., 101 KPa), at a current temperature of the supply module 20 (e.g., 40 ℃), and both the volume V and the amount of substance n are fixed values. Therefore, equation (1) can be derived:
101*V＝n*R*(40+273) (1)
As the ambient temperature drops, for example, the temperature of the supply module 20 drops to-15 ℃, equation (2) may be derived:
P*V＝nR*(-15+273) (2)
By basic mathematical transformation, the pressure in the pressure line 30 and the filter of the supply module 20 at-15 ℃ is obtained to be approximately p=83.3 KPa. Because the reservoir of exhaust aftertreatment agent is in communication with the outside atmosphere, the delivery valve 24 is subjected to a pressure differential ΔP of approximately 17.7KPa. Up to this point, from the pressure receiving area S of the delivery valve 24 (for example, 100mm 2), the pressure F (f=Δp×s, for example, 1.77N) to which the delivery valve 24 is subjected can be calculated. By setting the opening pressure p of the delivery valve 24 to be greater than the calculated pressure F, it is ensured that the delivery valve 24 is opened when receiving a pressure exceeding the opening pressure p.
The above is given by way of example only, and other calculations are possible depending on the piping arrangement and the configuration of the delivery valve. In addition, the opening pressure p required for the delivery valve 24 may also be measured directly by way of a test. However, in either case, for the above embodiment, the opening pressure p of the delivery valve 24 is derived based on the temperature change experienced by the supply module 20 after the evacuation phase.
A supply module according to an embodiment of the present application, which includes a diaphragm pump, is described in detail below with reference to fig. 2. As shown in fig. 2, the pump 23 is a diaphragm pump, and its upper structure includes a connection rod 231, a bearing 232, and an eccentric 233. The eccentric 233 is fixedly mounted to a drive shaft 234 of the motor and rotatably mounted within a bore of the connecting rod 231 by means of a bearing 232. When the driving shaft 234 of the motor rotates, the eccentric 233 and the inner parts of the bearing 232 rotate accordingly. Because of the eccentric configuration of the eccentric 233, the outer part of the bearing 232 and the connecting rod 231 are caused to move within a certain angle. The lower structure of the pump 23 includes a pump diaphragm 235, a pump diaphragm bracket 237 and a pump support 236, and the pump diaphragm 235 is fixed at its periphery by the pump diaphragm bracket 237 and the pump support 236, and is coupled at its center to the connection rod 231 and moves in a vertical direction with the movement of the connection rod 231. Thus, a pump chamber 238 is formed between the pump membrane 235 and the pump membrane mount 237. After the motor is started, the pump membrane 235 moves in the vertical direction along with the movement of the connecting rod 231, so that the pump chamber 238 expands and compresses once in one cycle of the movement of the pump membrane 235 in the vertical direction.
The pump diaphragm support 236 is coupled on its other side to the suction valve 22 and the delivery valve 24. As shown in fig. 2, the suction valve 22 is provided on the inlet side of the pump 23, and the delivery valve 24 is provided on the outlet side of the pump 23. The suction valve 22 includes a suction valve membrane 221, a suction valve inlet 222, and a suction valve outlet 223, and the suction valve membrane 221 is fixed at the suction valve outlet 223. The delivery valve 24 includes a delivery valve membrane 241, a delivery valve inlet 243, and a delivery valve outlet 242, the delivery valve membrane 241 being fixed at the delivery valve inlet 243. The suction valve 22 and the delivery valve 24 are provided in the same housing 230, but of course, the suction valve 22 and the delivery valve 24 may also each comprise separate housings. In addition, delivery valve 24 also includes an opening pressure setting device 240 disposed adjacent to delivery valve diaphragm 241. During the expansion phase of the pump chamber 238, the suction valve membrane 221 deforms under pressure, so that the suction channel of the suction valve 22 is opened, while the delivery valve membrane 241 remains closed. Thus, the exhaust aftertreatment agent flows in from the intake valve inlet 222 and flows in from the intake valve outlet 223 into the pump chamber 238 via the intake valve diaphragm 221. Referring also to fig. 2, during the compression phase of pump chamber 238, the exhaust aftertreatment within pump chamber 238 forces suction valve diaphragm 221 closed and opens delivery valve diaphragm 241 against the opening pressure p of delivery valve 24, thereby allowing the exhaust aftertreatment to flow from delivery valve inlet 243 and through delivery valve diaphragm 241 from delivery valve outlet 242 into pressure line 30.
In the embodiment shown in fig. 2, the suction valve membrane 221 and the delivery valve membrane 241 may be integrated into a single membrane, but may be separate membranes. During operation of pump 23, it is only necessary to ensure that only suction valve 22 is open and delivery valve 24 is closed during the expansion phase of pump chamber 238, and that only delivery valve 24 is open and suction valve 22 is closed during the compression phase of pump chamber 238, without specific restrictions on the specific flow path configurations of suction valve 22 and delivery valve 24.
In the embodiment shown, the opening pressure setting means 240 is a spring, which is set to a spring force. Of course, the opening pressure setting means 240 may be other structures, such as a means for providing gravity, magnetic force, or the like as the opening pressure. In addition, the opening pressure setting means 240 is adjustable, and the opening pressure p of the delivery valve 24 can be adjusted according to the need.
In the embodiment of the application, a feed module comprising a diaphragm pump is presented, but other pumping means, such as a plunger pump, gear pump, etc., may be used for the exhaust aftertreatment device. Accordingly, depending on the pump configuration, only the delivery valve 24 may be provided, and the suction valve 22 may not be provided. In these cases, the delivery valve 24 may be provided on the inlet side or the outlet side of the pump.
In the embodiment of the application, the exhaust gas aftertreatment agent is urea aqueous solution, but may be other catalytic reducing agents or any substances that react with the exhaust gas.
The operation of the supply module for exhaust gas aftertreatment and the exhaust gas aftertreatment device according to the application is described below with reference to fig. 1 and 2.
When the vehicle-mounted system detects that the tail gas of the vehicle exceeds the standard, the tail gas post-treatment device needs to be started. That is, the aqueous urea solution is injected into the exhaust pipe by the exhaust gas aftertreatment device so that the aqueous urea solution reacts with the exhaust gas.
During normal operation of the exhaust gas aftertreatment device, the reversing valve 21 of the supply module 20 is in the spring position. The aqueous urea solution enters the pump chamber 238 from the tank 10 via the suction line 70, the reversing valve 21, the suction valve 22 under the suction force of the pump 23 and is discharged from the delivery valve 24 into the pressure line 30 and thus into the injection module 40.
When the on-board system detects that the engine has been shut down or that the exhaust aftertreatment device needs to be shut down, for example due to another error, the system controls the reversing valve 21 to be in the electromagnetic force position, the injection valve in the injection module 40 is opened, and the pump 23 is operated. The urea aqueous solution flows back from the injection module 40, the pressure line 30 and the supply module 20 to the tank 10 under suction of the pump 23, evacuating the whole system and then shutting down the exhaust gas aftertreatment device.
When the entire system is shut down, the exhaust aftertreatment device is isolated from the external environment, except for the storage tank 10, with no air exchange. As the temperature decreases, the internal air pressure decreases compared to the air pressure of the external environment. This results in the creation of a negative pressure in the pressure line 30, the supply module 20 and the suction line 70, which may lead to a refilling phenomenon. Because the filter of the pressure line 30 and the supply module 20 has a larger volume than the suction line 70, the negative pressure in the filter of the pressure line 30 and the supply module 20 may be a major contributor to the occurrence of the refilling phenomenon. However, because the delivery valve 24 of the present application is configured to open only when the pressure p is open, the negative pressure within the pressure line 30 and the filter of the supply module 20 must exceed the opening pressure p to exert a force on the delivery valve 24 to the aqueous urea solution within the tank 10. Accordingly, by setting the opening pressure p of the delivery valve 24, it is possible to ensure that the negative pressure in the pressure line 30 and the filter of the supply module 20 is insufficient to open the delivery valve 24, thereby avoiding the occurrence of the refilling phenomenon.
According to the embodiment of the application, the opening pressure is set for the delivery valve of the supply module, so that the negative pressure in the pipeline of the exhaust gas aftertreatment device is insufficient to open the delivery valve, and therefore the exhaust gas aftertreatment agent is not led into the supply module along the suction pipeline. Thus, the occurrence of refilling is avoided, while the risk of damage to the feed module is eliminated. The application has simple structure, and only needs to change the structure of the delivery valve in the existing supply module or add the delivery valve.
The application has been described in detail with reference to specific embodiments thereof. It will be apparent that the embodiments described above and shown in the drawings are to be understood as illustrative and not limiting of the application. For example, the present application has been described in the preferred embodiment with respect to a supply module and exhaust aftertreatment device for engine exhaust aftertreatment, but may find application in any area where aftertreatment of exhaust gas is desired, not only in the engine area. It will be apparent to those skilled in the art that various modifications or variations can be made in the present application without departing from the spirit thereof, and that such modifications or variations do not depart from the scope of the application.
Claims (10)
1. A supply module (20) for exhaust aftertreatment, the supply module comprising:
A pump (23) configured to deliver an exhaust aftertreatment agent between the suction line (70) and the pressure line (30);
-a reversing valve (21) configured to switch between a normal operating phase, in which the exhaust aftertreatment agent flows from the suction line (70) to the pressure line (30), and an evacuation phase, in which the exhaust aftertreatment agent flows from the pressure line (30) to the suction line (70);
-a suction valve (22) for passing the exhaust aftertreatment agent flowing into the pump (23) in one direction;
-a delivery valve (24) for unidirectional passage of the exhaust aftertreatment discharged from the pump (23);
characterized in that the delivery valve (24) is configured to open at an opening pressure, which is derived based on the temperature change to which the supply module (20) is subjected after the evacuation phase.
2. The supply module (20) of claim 1, wherein the delivery valve (24) includes an opening pressure setting device (240) capable of adjusting an opening pressure of the delivery valve.
3. The supply module (20) according to claim 1 or 2, characterized in that the suction valve (22) is arranged on the inlet side of the pump (23) and the delivery valve (24) is arranged on the outlet side of the pump (23).
4. The supply module (20) according to claim 1 or 2, characterized in that the supply module (20) further comprises a filter downstream of the delivery valve (24) in the normal operating phase, which filter communicates with the pressure line (30).
5. A supply module (20) according to claim 3, characterized in that the pump (23) is a diaphragm pump and the suction valve (22) and the delivery valve (24) are diaphragm valves.
6. The supply module (20) of claim 1 or 2, wherein the opening pressure is at least one of gravity, spring force, magnetic force.
7. The supply module (20) of claim 1, wherein the delivery valve (24) includes: a housing (230) provided with a delivery valve inlet (243) and a delivery valve outlet (242); -a delivery valve membrane (241) fixed at the delivery valve inlet (243); a spring disposed adjacent to the delivery valve membrane (241) to provide the opening pressure.
8. An exhaust aftertreatment device comprising:
a tank (10) for storing an exhaust aftertreatment agent;
an injection module (40) for injecting the exhaust aftertreatment agent;
The supply module (20) according to any one of claims 1-7, for supplying the exhaust aftertreatment agent from the reservoir (10) to the injection module (40);
-a suction line (70) connected between the tank (10) and the supply module (20); and
-A pressure line (30) connected between the supply module (20) and the injection module (40).
9. The exhaust aftertreatment device of claim 8, further comprising a return line (60), the return line (60) being coupled between the supply module (20) and the tank (10).
10. The exhaust aftertreatment device of claim 9, wherein a return connection (50) is provided in the return line (60), the return connection (50) comprising a throttle valve and a one-way valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710675298.XA CN109386352B (en) | 2017-08-09 | 2017-08-09 | Supply module for exhaust gas aftertreatment and exhaust gas aftertreatment device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710675298.XA CN109386352B (en) | 2017-08-09 | 2017-08-09 | Supply module for exhaust gas aftertreatment and exhaust gas aftertreatment device |
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| CN109386352A CN109386352A (en) | 2019-02-26 |
| CN109386352B true CN109386352B (en) | 2024-05-03 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6358412B1 (en) * | 1999-01-21 | 2002-03-19 | Robert Bosch Gmbh | Feed system for fuel |
| DE102012214369A1 (en) * | 2012-08-13 | 2014-02-13 | Robert Bosch Gmbh | Exhaust aftertreatment arrangement for internal combustion engine of motor vehicle, has storage with piston arranged between conveying unit and injection valve, where reducing agent is conveyed from storage in direction of exhaust line |
| CN105121800A (en) * | 2013-02-13 | 2015-12-02 | 大陆汽车有限责任公司 | Method for providing a liquid additive |
| DE102015208565A1 (en) * | 2015-05-08 | 2016-11-10 | Robert Bosch Gmbh | Hydraulic conveying and dosing system and method for operating the hydraulic conveying and dosing system |
| CN106762048A (en) * | 2017-01-18 | 2017-05-31 | 重庆凯瑞伟柯斯环保科技有限公司 | Pumping unit and the urea liquid feed system and method for SCR system crystallization-preventive |
| CN207145038U (en) * | 2017-08-09 | 2018-03-27 | 博世汽车柴油系统有限公司 | Supplying module and tail-gas after treatment apparatus for exhaust aftertreatment |
-
2017
- 2017-08-09 CN CN201710675298.XA patent/CN109386352B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6358412B1 (en) * | 1999-01-21 | 2002-03-19 | Robert Bosch Gmbh | Feed system for fuel |
| DE102012214369A1 (en) * | 2012-08-13 | 2014-02-13 | Robert Bosch Gmbh | Exhaust aftertreatment arrangement for internal combustion engine of motor vehicle, has storage with piston arranged between conveying unit and injection valve, where reducing agent is conveyed from storage in direction of exhaust line |
| CN105121800A (en) * | 2013-02-13 | 2015-12-02 | 大陆汽车有限责任公司 | Method for providing a liquid additive |
| DE102015208565A1 (en) * | 2015-05-08 | 2016-11-10 | Robert Bosch Gmbh | Hydraulic conveying and dosing system and method for operating the hydraulic conveying and dosing system |
| CN106762048A (en) * | 2017-01-18 | 2017-05-31 | 重庆凯瑞伟柯斯环保科技有限公司 | Pumping unit and the urea liquid feed system and method for SCR system crystallization-preventive |
| CN207145038U (en) * | 2017-08-09 | 2018-03-27 | 博世汽车柴油系统有限公司 | Supplying module and tail-gas after treatment apparatus for exhaust aftertreatment |
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| CN109386352A (en) | 2019-02-26 |
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Address after: 214028 No.17 Xinhua Road, national high tech Industrial Development Zone, Wuxi City, Jiangsu Province Applicant after: Bosch powertrain Co.,Ltd. Address before: 214028 No.17 Xinhua Road, national high tech Industrial Development Zone, Wuxi City, Jiangsu Province Applicant before: Bosch Automotive Diesel Systems Co.,Ltd. |
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