CN111535910A

CN111535910A - Solution spraying system and engineering machinery

Info

Publication number: CN111535910A
Application number: CN202010520680.5A
Authority: CN
Inventors: 马先锋; 钟佩文; 李亚锋
Original assignee: Sany Heavy Machinery Ltd
Current assignee: Sany Heavy Machinery Ltd
Priority date: 2020-06-09
Filing date: 2020-06-09
Publication date: 2020-08-14

Abstract

The invention relates to the field of engineering machinery, in particular to a solution spraying system and engineering machinery; the solution spraying system comprises a solution tank and a spraying assembly, wherein the solution tank comprises a pressure chamber and a pressing and sucking chamber which are distributed along the vertical direction inside, and the pressing and sucking chamber is connected with the spraying assembly; wherein, the inside of the solution tank is movably provided with a piston which separates a pressure chamber from a pressing-out suction chamber; when the pressure chamber is pressurized, the piston can be pushed to compress and extrude the solution in the suction chamber, so that the solution extruded and sucked in the chamber is pressed into the spraying component; when the pressure chamber is depressurized, the piston can compress the space of the pressure chamber and the solution in the jetting assembly can flow into and out of the suction chamber. The solution spraying system does not need to be provided with an air compressor or a heating device for the spraying assembly, so that the structure can be simplified, and the cost can be reduced.

Description

Solution spraying system and engineering machinery

Technical Field

The invention relates to the field of engineering machinery, in particular to a solution spraying system and engineering machinery.

Background

In order to meet the emission requirements of engineering machinery, catalytic reaction on engine exhaust is required, and a solution injection system is further required to be configured for injecting urea.

However, the solution spraying system provided by the related art needs to be provided with an air compressor and a heating device for the spraying assembly, which leads to the problems of complex structure and high cost of the solution spraying system.

Disclosure of Invention

The invention aims to provide a solution spraying system and engineering machinery, which can simplify the structure and reduce the cost.

The embodiment of the invention is realized by the following steps:

in a first aspect, an embodiment of the present invention provides a solution spraying system, including a solution tank and a spraying module, where the solution tank includes a pressure chamber and a pressing-out and suction chamber distributed in an up-and-down direction, and the pressing-out and suction chamber is connected to the spraying module; wherein, the inside of the solution tank is movably provided with a piston which separates a pressure chamber from a pressing-out suction chamber; when the pressure chamber is pressurized, the piston can be pushed to compress and extrude the solution in the suction chamber, so that the solution extruded and sucked in the chamber is pressed into the spraying component; when the pressure chamber is depressurized, the piston can compress the space of the pressure chamber and the solution in the jetting assembly can flow into and out of the suction chamber.

In an alternative embodiment, the pressure chamber is provided with a first heating device, and the pressure chamber can be filled with a phase-change medium, and the first heating device is used for heating the phase-change medium filled in the pressure chamber to sublimate or evaporate the phase-change medium, so as to pressurize the pressure chamber.

In an alternative embodiment, the injection assembly comprises a spray head, an injection pipeline and a filter element arranged in the injection pipeline, one end of the injection pipeline is communicated with the extrusion and suction chamber, and the other end of the injection pipeline is connected with the spray head.

In an alternative embodiment, the spray assembly further comprises a pressure valve disposed in the spray conduit, the pressure valve being located upstream of the filter element in a direction of flow of the solution in the spray conduit when the spray assembly sprays the solution.

In an alternative embodiment, the spray assembly further comprises a regulating valve disposed in the spray conduit, the regulating valve being located upstream of the spray head in a direction of flow of the solution in the spray conduit when the spray assembly sprays the solution.

In an alternative embodiment, the spray assembly further comprises a pressure sensor disposed in the spray conduit, and the regulating valve is located between the spray head and the pressure sensor along a flow direction of the solution in the spray conduit when the spray assembly sprays the solution.

In an alternative embodiment, the interior of the solution tank further comprises a storage chamber located below the extruding and sucking chamber, and the extruding and sucking chamber is connected with the storage chamber through a pipe provided with a check valve for preventing the solution in the extruding and sucking chamber from flowing to the storage chamber.

In an alternative embodiment, one end of the conduit communicates with the expression suction chamber from the bottom end thereof, and the other end of the conduit extends into the storage chamber.

In an alternative embodiment, the reservoir is provided with a breather valve and a solution injection port.

In an alternative embodiment, the pressure-extraction suction chamber is provided with a second heating device.

In a second aspect, an embodiment of the present disclosure provides a working machine including the solution spraying system according to any one of the foregoing embodiments.

The solution spraying system of the embodiment of the invention has the beneficial effects that: the solution spraying system comprises a solution tank, wherein the solution tank comprises a pressure chamber and a pressing and sucking chamber which are distributed along the vertical direction, a piston is movably arranged in the solution tank, and the piston separates the pressure chamber from the pressing and sucking chamber; when the pressure chamber is pressurized, the piston can be pushed to compress and extrude the solution in the suction chamber, so that the solution extruded and sucked in the chamber is pressed into the spraying component; when the pressure chamber is decompressed, the piston can compress the space of the pressure chamber, and the solution in the injection assembly can flow into the extrusion suction chamber; therefore, when the solution injection system is used for injecting urea, the solution in the extrusion and suction chamber can be pressed into the injection assembly for injecting the solution only by pressurizing the pressure chamber and pushing the piston to compress and extrude the solution in the extrusion and suction chamber, and components such as an air compressor and the like are not required to be arranged; when the pressure chamber is depressurized, the solution in the injection assembly can flow into the extrusion suction chamber and can not remain in the injection assembly, so that the solution which is easy to crystallize and is urea is prevented from remaining in the injection assembly, namely, a heating device is not separately arranged on the injection assembly, and the injection assembly can be prevented from being blocked; because, this solution injection system need not dispose the air compressor machine, also need not alone to give injection subassembly configuration heating device, then can simplify the structure, reduce cost.

The engineering machinery of the embodiment of the invention has the beneficial effects that: the engineering machinery provided by the embodiment of the invention comprises the solution spraying system, and the engineering machinery can spray urea by using the solution spraying system so as to enable tail gas exhausted by an engine to generate a catalytic reaction, thereby meeting the emission requirement; the solution spraying system arranged on the engineering machinery has simple structure and low cost.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a solution ejection system in an embodiment of the present invention.

Icon: 010-solution spraying system; 100-solution tank; 200-a spray assembly; 110-a pressure chamber; 120-pressing out the suction chamber; 130-a piston; 111-a first heating device; 112-a phase change medium; 121-a spray head; 122-an injection conduit; 123-a filter element; 124-a pressure valve; 125-regulating valve; 126-a pressure sensor; 140-a storage compartment; 141-a pipeline; 142-a one-way valve; 143-a breathing valve; 144-solution injection port; 145-a second heating device; 146-the trachea; 150-ECU; 151-exhaust pipe; 152-a catalytic reduction reaction chamber; 153-temperature sensor.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships conventionally put in use of products of the present invention, and are only for convenience of description and simplification of description, but do not indicate or imply that the devices or elements referred to must have specific orientations, be constructed in specific orientations, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical" and the like do not imply that the components are required to be absolutely horizontal or pendant, but rather may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed" and "connected" are to be interpreted broadly, e.g., as being either fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

First embodiment

Referring to fig. 1, the present embodiment provides a construction machine, which may be an excavator, a crane, or the like.

The engineering machine includes an Electronic Control Unit (ECU 150, also called a traveling computer or a vehicle-mounted computer), an engine, and a solution injection system 010. In order to meet the standard of exhaust emission of the engine, the solution injection system 010 is required to inject urea into the exhaust pipe 151 of the engine, so that the exhaust of the engine can be exhausted after catalytic reaction, and the requirement of exhaust emission is met; further, the engine includes an exhaust pipe 151 for discharging exhaust gas, the exhaust pipe 151 is provided with a catalytic reduction reaction chamber 152, and the solution injection system 010 can inject urea into the catalytic reduction reaction chamber 152 to catalytically react the urea with the exhaust gas.

Referring to fig. 1, the solution spraying system 010 of the present embodiment includes a solution tank 100 and a spraying assembly 200, wherein the solution tank 100 is used for containing a solution, for example: urea and the like; the solution tank 100 includes a pressure chamber 110 and an extrusion/suction chamber 120 distributed in the vertical direction, and the extrusion/suction chamber 120 is connected to the spray module 200; wherein, a piston 130 is movably disposed inside the solution tank 100, and the piston 130 separates the pressure chamber 110 and the extruding-sucking chamber 120; when the pressure chamber 110 is pressurized, the piston 130 can be pushed to compress the solution in the suction chamber 120, so as to press the solution in the suction chamber 120 into the spray assembly 200; when the pressure chamber 110 is depressurized, the piston 130 can compress the space of the pressure chamber 110 and the solution in the spray assembly 200 can flow into and out of the suction chamber 120.

When the solution injection system 010 of the embodiment injects urea, the solution in the suction chamber 120 can be pressed into the injection assembly 200 to inject the solution by pressurizing the solution in the pressure chamber 110 and pushing the piston 130 to compress and extrude the solution in the suction chamber 120 without arranging parts such as an air compressor and the like; when the pressure chamber 110 is depressurized, the solution in the injection module 200 can flow into the pressure outlet chamber 120 without remaining in the injection module 200, so as to prevent the solution, which is easily crystallized, from remaining in the injection module 200, i.e., the injection module 200 may not be separately provided with a heating device, and the injection module 200 may be prevented from being clogged; because, this solution injection system 010 need not dispose the air compressor machine, also need not alone to dispose heating device for injection subassembly 200, then can simplify the structure, reduce cost.

It should be noted that, because the solution ejection system 010 of this embodiment does not need to be provided with devices such as an air compressor, and further, the problems such as air compressor failure and damage do not occur, the solution ejection system 010 does not need to maintain the air compressor, and the difficulty and cost of maintenance are reduced.

Referring to fig. 1, the pressure chamber 110 of the present embodiment is provided with a first heating device 111, and the pressure chamber 110 is filled with a phase-change medium 112, and the first heating device 111 is used for heating the phase-change medium 112 filled in the pressure chamber 110 to sublimate or evaporate the phase-change medium 112, so as to pressurize the pressure chamber 110. When the first heating device 111 does not heat the phase change medium 112 any more, the temperature of the phase change medium 112 gradually decreases, and the phase change medium is solidified or liquefied again, thereby reducing the pressure in the pressure chamber 110. In this way, the first heating device 111 can conveniently control the pressurization or depressurization of the pressure chamber 110 to control the piston 130 to compress and extrude the suction chamber 120 or the compression pressure chamber 110 by the pressurization or depressurization of the pressure chamber 110, so as to press the solution extruded from the suction chamber 120 into the spray module 200 or to enable the solution extruded from the spray module 200 to flow back to the extrusion chamber 120.

The phase change medium 112 filled in the pressure chamber 110 may be in a solid state or a liquid state. When the phase change medium 112 filled in the pressure chamber 110 is in a solid state, the first heating device 111 heats to sublimate the phase change medium 112; when the first heating means 111 is no longer heated and the temperature in the pressure chamber 110 drops, the phase change medium 112 solidifies again. When the pressure chamber 110 is filled with the phase change medium 112 in a liquid state, the first heating device 111 heats to evaporate the phase change medium 112; when the first heating means 111 is no longer heated and the temperature in the pressure chamber 110 drops, the phase change medium 112 liquefies again.

The phase change medium 112 may be selected according to need, cost, etc., and may be, for example: acetone, ethanol, difluoromethane chloride (R22), etc., and are not particularly limited herein.

It should be noted that, the pressure chamber 110 of the present embodiment is located above the extruding and sucking chamber 120, when the phase-change medium 112 in the pressure chamber 110 sublimates or evaporates, the gas in the pressure chamber 110 pushes the piston 130 to move downward, so as to extrude the solution in the extruding and sucking chamber 120 by the piston 130, thereby the solution extruded in the extruding and sucking chamber 120 can be pressed into the spraying device; when the pressure chamber 110 cools down and the phase change medium 112 is solidified or liquefied again, the gas in the pressure chamber 110 decreases, and the gas in the pressure chamber 110 no longer presses the piston 130 downward, and the piston 130 moves upward to compress the space of the pressure chamber 110.

In order to enable the phase change medium 112 filled in the pressure chamber 110 to be heated and sublimated or evaporated better, the first heating device 111 is disposed inside the pressure chamber 110 to heat the phase change medium 112 in the pressure chamber 110 sufficiently.

Referring to fig. 1, the injection assembly 200 of the present embodiment includes an injection head 121, an injection pipe 122 and a filter element 123 disposed in the injection pipe 122, wherein one end of the injection pipe 122 is communicated with the extrusion and suction chamber 120, and the other end is connected to the injection head 121. Thus, the pressure in the pressure chamber 110 can be increased, the piston 130 is pushed to press the solution pressed out of the suction chamber 120 into the injection pipe 122, and the solution entering the injection pipe 122 can pass through the filter element 123 and then be injected from the injection head 121; the filter element 123 is capable of filtering out impurities in the solution and preventing the downstream of the conduit 141 downstream of the filter element 123 from being blocked.

It should be noted that the injection pipe 122 is disposed adjacent to the bottom of the extruding chamber 120, so that the solution extruded from the extruding chamber 120 is smoothly pressed into the injection pipe 122 when the piston 130 is pushed downward by pressurizing the pressure chamber 110.

It should be further noted that the spray head 121 is disposed in the exhaust pipe 151 of the engine, and the spray head 121 is located upstream of the catalytic reduction reaction chamber 152 along the flowing direction of the exhaust gas discharged from the engine in the exhaust pipe 151, so that the urea injected by the solution injection system 010 can react with the exhaust gas discharged from the exhaust pipe 151 in the catalytic reduction reaction chamber 152, and then the exhaust gas which meets the emission standard after the catalytic reaction is discharged from the catalytic reduction reaction chamber 152.

Referring to fig. 1, the injection assembly 200 further includes a pressure valve 124 disposed in the injection pipe 122, and the pressure valve 124 is located upstream of the filter element 123 along a direction in which the solution flows in the injection pipe 122 when the injection assembly 200 injects the solution. The pressure valve 124 is configured such that when the solution pressed out of the suction chamber 120 is pressed into the injection pipe 122, and when the solution in the injection pipe 122 flows to the spray head 121, the pressure valve 124 is opened, so that the solution in the injection pipe 122 can smoothly flow to the spray head 121, when the pressure chamber 110 is depressurized, the piston 130 compresses the space of the pressure chamber 110, the entire solution in the injection pipe 122 flows back out of the suction chamber 120, and when there is no more solution in the injection pipe 122, the pressure valve 124 is closed, i.e., the pressure valve 124 does not pass gas, i.e., the pressure valve 124 is closed when gas passes through the pressure valve 124, so as to prevent gas such as exhaust gas from entering the pressure-out suction chamber 120, prevent interference with the normal operation of the piston 130 and the pressure chamber 110, i.e., to prevent gas from entering the pressure-out suction chamber 120, to prevent the pressure of the pressure-out suction chamber 120 from being changed, thereby preventing the piston 130 from being unable to normally compress and extrude the solution in the suction chamber 120 when the pressure chamber 110 is pressurized.

The pressure valve 124 of this embodiment is selected to be a trap that is capable of opening when a solution flows therethrough, i.e., passing the solution, and is capable of closing when a gas flows therethrough, i.e., not passing the gas. In other embodiments, the pressure valve 124 may also be a general-purpose solenoid valve, and the solenoid valve is connected to the ECU150 in communication, so that the ECU150 controls the opening and closing of the solenoid valve, that is, the ECU150 controls the solenoid valve to open when the solution flows through and close when the gas flows through.

Referring to fig. 1, the spraying assembly 200 of the present embodiment further includes a regulating valve 125 disposed in the spraying pipe 122, and the regulating valve 125 is located upstream of the spraying head 121 along a flowing direction of the solution in the spraying pipe 122 when the spraying assembly 200 sprays the solution. Therefore, when the pressure chamber 110 is pressurized to push the piston 130 to compress the solution out of the suction chamber 120, so that the solution enters the injection assembly 200, the regulating valve 125 is used to control the amount of the solution injected by the nozzle 121, so that the amount of the solution injected by the solution injection system 010 more meets the working condition, and the waste and insufficient injection amount of the solution are reduced.

Further, the regulating valve 125 is in communication connection with the ECU150, so that the ECU150 is utilized to control the opening degree of the regulating valve 125, and thus, different amounts of solution are sprayed; for example: when the engine emits more exhaust gas, the ECU150 controls the opening degree of the regulating valve 125 to increase to inject more urea, so that the exhaust gas can be sufficiently catalytically reacted to help the engine meet the emission standard; when the exhaust gas discharged by the engine is less, the ECU150 controls the opening degree of the regulating valve 125 to decrease so as to inject a small amount of urea, and thus the catalytic reaction of the exhaust gas can be satisfied, and the waste of urea can be reduced.

Referring to fig. 1, the spraying assembly 200 of the present embodiment further includes a pressure sensor 126 disposed in the spraying pipe 122, and the regulating valve 125 is located between the spraying head 121 and the pressure sensor 126 along the flowing direction of the solution in the spraying pipe 122 when the spraying assembly 200 sprays the solution. In this way, when the solution pressed out of the suction chamber 120 is pressed into the injection pipe 122, the pressure of the solution in the injection pipe 122 is detected by the pressure sensor 126, so that the regulating valve 125 is controlled to be opened to spray the solution in the injection pipe 122 after the pressure sensor 126 detects that the pressure in the injection pipe 122 satisfies the preset pressure.

Further, the pressure sensor 126 is in communication connection with the ECU150, so that after the pressure in the injection pipe 122 detected by the pressure sensor 126, a corresponding first signal can be sent to the ECU150, so that the ECU150 can determine the pressure in the injection pipe 122 according to the received first signal, and control the regulating valve 125 to open when the pressure in the injection pipe 122 is determined to meet the preset pressure. When the ECU150 determines that the pressure in the injection pipe 122 does not reach the preset pressure based on the received first signal transmitted from the pressure sensor 126, the ECU150 controls the regulating valve 125 to be kept in the closed state.

Please refer to fig. 1, the exhaust pipe 151 of the engine of the present embodiment is further provided with a temperature sensor 153, and the temperature sensor 153 is used for detecting the temperature of the exhaust gas discharged from the exhaust pipe 151; further, the temperature sensor 153 is in communication connection with the ECU150, so that after the temperature sensor 153 detects the temperature of the exhaust gas, a corresponding second signal is sent to the ECU150, and the ECU150 determines whether the temperature of the exhaust gas in the exhaust pipe 151 reaches a preset temperature according to the second signal. It should be further noted that, when the engine is operated and urea is injected by the solution injection system 010 to make the catalytic reaction of the exhaust gas reach the emission standard, the ECU150 is required to determine that the pressure of the injection pipe 122 reaches the preset pressure according to the first signal, and determine that the temperature of the exhaust gas in the exhaust pipe 151 reaches the preset temperature according to the second signal, and then control the regulating valve 125 to open.

The communication connection includes a wireless communication connection such as WiFi, bluetooth, and infrared, and also includes a wired communication connection using a cable, which is not limited herein.

Referring to fig. 1, the solution tank 100 of the present embodiment further includes a storage chamber 140 located below the extruding and sucking device, the extruding and sucking chamber 120 is connected to the storage chamber 140 through a pipe 141 provided with a check valve 142, and the check valve 142 is used to prevent the solution extruded from the extruding and sucking chamber 120 from flowing to the storage chamber 140. After the solution ejection system 010 finishes the ejection of the solution, the first heating means 111 of the pressure chamber 110 stops heating, the temperature of the pressure chamber 110 drops, the phase change medium 112 solidifies or liquefies, the pressure chamber 110 decompresses, the piston 130 compresses the space of the pressure chamber 110, i.e., the piston 130 moves upward, compressing the space of the pressure chamber 110, the solution in the spray assembly 200 flows back to the extruding-out suction chamber 120, and since a portion of the solution originally stored in the extruding-out suction chamber 120 is sprayed, even if the solution remaining in the spray assembly 200 flows back to the extruding-suction chamber 120, the pressure in the extruding-suction chamber 120 is reduced, so that the solution stored in the storage chamber 140 is sucked into and pressed out of the suction chamber 120 through the pipe 141 provided with the check valve 142, to perform automatic solution replenishment and restore the pressure of the pressure-out suction chamber 120 to the initial state, i.e., to the state of the solution not being injected, so as to meet the demand of the next injection of the solution.

Further, one end of the duct 141 is communicated with the push-out suction chamber 120 from the bottom end of the push-out suction chamber 120, and the other end of the duct 141 is extended into the storage chamber 140. When the pressure chamber 110 is depressurized in this manner, the piston 130 moves upward, and the solution stored in the storage chamber 140 can be sucked into the extrusion chamber 120 from the bottom of the extrusion chamber 120 through the pipe 141 provided with the check valve 142.

The storage chamber 140 of the present embodiment is provided with a breather valve 143 and a solution injection port 144. The breather valve 143 may be used to maintain a stable pressure within the storage chamber 140; specifically, when the pressure chamber 110 is depressurized to move the piston 130 upward, the solution in the storage chamber 140 is sucked and pressed out of the suction chamber 120, and then the external air can enter the storage chamber 140 through the breather valve 143, thereby ensuring that the pressure in the storage chamber 140 is maintained stably. The solution inlet 144 is used to supply the solution to the storage chamber 140, so that the storage chamber 140 is prevented from being short of the solution.

Further, referring to fig. 1, the breather valve 143 is disposed at an upper portion of the storage chamber 140, so that gas can flow between the inside and the outside of the storage chamber 140 through the breather valve 143, and the solution in the storage chamber 140 cannot flow out of the storage chamber 140 through the breather valve 143. Still further, the storage chamber 140 is communicated with an air pipe 146, one end of the air pipe 146, which is far away from the storage chamber 140, extends to the upper part of the storage chamber 140 and extends out of the top end of the storage chamber 140, and one end of the air pipe 146, which is far away from the storage chamber 140, is provided with the breather valve 143.

Further, the solution inlet 144 is provided at a lower portion thereof, so that the solution can be easily supplied to the storage chamber 140, and the solution in the storage chamber 140 can be discharged from the solution inlet 144 when the solution injection system 010 is not required to be used.

In order to avoid crystallization of the solution pressed out of the suction chamber 120, for example: urea is easy to crystallize in a low-temperature environment; referring to fig. 1, the extruding and sucking chamber 120 of the present embodiment is provided with a second heating device 145 for heating the solution contained in the extruding and sucking chamber 120 to avoid low temperature crystallization. Further, the second heating device 145 is disposed inside the extrusion suction chamber 120 to more sufficiently warm the solution inside the extrusion suction chamber 120.

It should be noted that, the first heating device 111 and the second heating device 145 may be heating resistance wires, heating rods, and the like, and are not limited in particular.

When the engine of the construction machine is in operation, the solution tank 100 of the solution injection system 010 contains urea; the first heating device 111 is electrified to start heating, the phase change medium 112 in the pressure chamber 110 is sublimated or evaporated, the pressure chamber 110 is pressurized, the piston 130 is pushed to move downwards, so that the urea extruded from the suction chamber 120 is pressed into the injection pipeline 122, the pressure sensor 126 arranged on the injection pipeline 122 detects the pressure value in the injection pipeline 122, a corresponding first signal is sent to the ECU150, the ECU150 judges that the pressure detected by the pressure sensor 126 is the preset pressure, meanwhile, the temperature sensor 153 sends a second signal to the ECU150, when the ECU150 judges that the exhaust temperature reaches the preset temperature, the ECU150 controls the regulating valve 125 to be opened, and the urea filtered by the filter element 123 in the injection pipeline 122 can be injected into the catalytic reduction reaction chamber 152.

When the construction machine is stopped, the first heating device 111 stops heating, the temperature in the pressure chamber 110 drops, the phase change medium 112 is solidified or liquefied again, the pressure in the pressure chamber 110 decreases, the piston 130 moves upwards, the urea in the injection pipeline 122 flows back to the extrusion suction chamber 120, and the urea in the storage chamber 140 is sucked into the extrusion suction chamber 120 through the pipeline 141 provided with the check valve 142, so that the extrusion suction chamber 120 is replenished with urea; in order to prevent urea in the extruding and sucking chamber 120 from crystallizing, when the apparatus is stopped, the power of the second heating device 145 is turned on, and the urea in the extruding and sucking chamber 120 is heated by the second heating device 145.

In summary, the solution injection system 010 of the engineering machine of the present invention does not need to be equipped with an air compressor, and does not need to be equipped with a heating device for the injection assembly 200, so as to simplify the structure and reduce the cost.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The solution spraying system is characterized by comprising a solution tank and a spraying assembly, wherein the solution tank internally comprises a pressure chamber and an extrusion and suction chamber which are distributed along the vertical direction, and the extrusion and suction chamber is connected with the spraying assembly;

wherein, a piston is movably arranged in the solution tank, and the piston separates the pressure chamber from the extrusion and suction chamber;

when the pressure chamber is pressurized, the piston can be pushed to compress the solution in the extrusion and suction chamber so as to press the solution in the extrusion and suction chamber into the spraying component; when the pressure chamber is decompressed, the piston can compress the space of the pressure chamber, and the solution in the injection assembly can flow into the extrusion and suction chamber.

2. The solution spraying system as claimed in claim 1, wherein the pressure chamber is provided with a first heating device, and the pressure chamber can be filled with a phase-change medium, and the first heating device is configured to heat the phase-change medium filled in the pressure chamber to sublimate or evaporate the phase-change medium, so as to pressurize the pressure chamber.

3. The solution injection system according to claim 1, wherein the injection assembly comprises an injection head, an injection pipeline and a filter element arranged in the injection pipeline, one end of the injection pipeline is communicated with the extrusion and suction chamber, and the other end of the injection pipeline is connected with the injection head.

4. The solution injection system of claim 3, wherein the injection assembly further comprises a pressure valve disposed in the injection conduit, the pressure valve being located upstream of the filter element in a direction of flow of the solution in the injection conduit when the injection assembly injects the solution.

5. The solution injection system of claim 3, wherein the injection assembly further comprises a regulating valve disposed in the injection conduit, the regulating valve being located upstream of the spray head in a direction of flow of the solution in the injection conduit when the injection assembly injects the solution.

6. The solution spraying system of claim 5, wherein the spray assembly further comprises a pressure sensor disposed in the spray conduit, the regulating valve being positioned between the spray head and the pressure sensor in a direction of flow of the solution in the spray conduit when the spray assembly sprays the solution.

7. The solution spray system as claimed in claim 1, wherein the inside of the solution tank further comprises a storage chamber located below the extruding and sucking chamber, and the extruding and sucking chamber is connected to the storage chamber through a pipe provided with a check valve for preventing the solution in the extruding and sucking chamber from flowing to the storage chamber.

8. The solution spray system as claimed in claim 7, wherein said storage chamber is provided with a breather valve and a solution injection port.

9. Solution ejection system according to any one of claims 1-8, wherein the pressure-suction chamber is provided with a second heating means.

10. A working machine comprising a solution injection system according to any one of claims 1 to 9.