KR20120118888A - Urea level-sender unit and urea storing and supplying apparatus - Google Patents

Abstract

PURPOSE: An urea level sender unit and a device for supplying and storing urea with the same are provided to rapidly defrost urea without driving an engine, and to stably supply the urea. CONSTITUTION: An urea level sender unit(100) comprises a level sender head(102), a float(141), a PCB substrate housing(143), a connector(111) at the urea suction side, a connector(121) at the urea return side, a filter(161), a filter housing(162), and a heating pad. The filter is connected to the connector at the urea suction side. The filter housing encloses the filter. The heating pad comprises a heating pad body, a plurality of straps, and a power cable(14). The heating pad is made of rubber or insulation resin, and comprises heating elements inside. The straps are extended from one side of the heating pad, and comprise a constant width. The power cable is electrically connected to the heating element. The heating pad is attached to the inner wall of a level sender body.

Description

Urea level-sender unit and urea storing and supplying apparatus including the same

The present invention relates to a device for exhaust gas aftertreatment of a diesel vehicle, and more particularly, to a level sender unit mounted to a urea water storage tank of an exhaust gas aftertreatment system of an SCR method. It can not only measure the level and temperature of urea water accurately in real time, but also prevent the urea water from freezing and freezing in winter or cold season, and if urea water freezes quickly, An improved urea water level sender unit for supplying water to a dosing unit and a urea water storage and supply device including the same.

Recently, environmental pollution has become a major issue, and in the case of automobiles, electric cars, hydrogen cars, solar cars, and hybrid cars, which are eco-friendly cars that do not use fossil fuels, are being actively developed and marketed.

However, despite the emergence of such eco-friendly cars, automobiles that use gasoline or diesel as fuels still dominate the automobile market and are expected to remain in the market for a long time.

As such, in the case of an internal combustion engine vehicle using fossil fuels such as gasoline or diesel, there is a problem that environmental pollution due to exhaust gas is serious. Particularly in the case of diesel cars such as buses and trucks, the emission of particulate matter, NOx and fine dust including soot is recognized as a serious problem. There is a regulation that strictly regulates the emission of exhaust gas.

As a method of treating exhaust gas of a diesel engine, a diesel particulate filter (DPF) method for removing fine dust including an oxidation catalyst method and a NOx catalyst method soot is known. Diesel engines operate in excess air in most areas, releasing large amounts of oxygen in the exhaust. The method of reducing NOx based on the presence of oxygen includes a method of selectively decomposing NOx using a SCR (Selective Catalytic Reduction) catalyst coated with copper or iron ions and a reducing agent ammonia.

In the SCR system, ammonia is generated by using urea (urea) instead of reducing agent ammonia gas, and the urea water stored in the urea water storage tank is used as much as necessary. It is automatically supplied with the urea water, which usually consumes about 4% of the urea water compared to the fuel consumption.

Since the urea water in the urea water storage tank may be frozen and not operate in winter or cold season, a heating structure is required to prevent freezing of urea water.

6 shows a conventional urea tube heating structure, which is disclosed in Korean Patent Application Publication No. 10-2008-0075638 "Tube Heating Structure of Urea SRC System". The above-mentioned patent discloses a structure for heating urea (urea water) by flowing heated coolant circulating in an engine into a urea tank and bringing the coolant tube into contact with the urea tube and exchanging heat.

On the other hand, Patent Publication No. 10-2006-0059400 "Urea aqueous solution freezing prevention structure using the exhaust gas of the engine" and Patent Publication No. 10-2007-0059641 "Urea water storage tank heating device of the diesel engine" is discharged from the engine The structure which heats urea water by heat-exchanging with a urea water storage tank using the residual heat of exhaust gas which is a high heat source is disclosed.

Fig. 7 is a block diagram of an apparatus for supplying urea water according to another embodiment of the related art, which is disclosed in Korean Patent No. 0792927, “SCR Post-Processing Element Supply Device”. According to the registered patent, a main heating device is provided in the main element tank, and an auxiliary heating device is provided in the auxiliary element tank, and the elements are provided for quickly thawing and supplying the urea water to the auxiliary heating device at the beginning of cold start by connecting them with a directional valve. A water supply device is disclosed.

However, since the conventional urea water heating structures require a separate piping structure for circulating the cooling water or circulating the exhaust gas, there is a problem in that it is inconvenient in that it is necessary to change the structure of the vehicle and increases the cost. This structure has a problem in that it takes a long time to operate normally in the early stage of cold start because the engine must be heated to a certain extent so that the engine can be thawed to supply frozen urea water.

In the case of an electric patent using an auxiliary heating device, there is an advantage in that the urea water can be thawed and supplied without starting the engine in the early stage of cold start, but additional installation place or cost may be required in the case of providing the auxiliary heating device separately. In addition, the piping is complicated, it requires a separate control device for controlling the directional valve or the flow control valve solenoid valve is not cost-effective and there is a limit to the existing vehicle.

Therefore, the structure is simple and cost-effective, and it can be easily attached and detached to the urea water tank, so it is excellent to be mounted on the vehicle, and the freezing of urea water can be prevented without a separate pipe or auxiliary tank, and the frozen urea water is engined. The development of an improved sensor unit for urea tanks has been called for to thaw and feed quickly without driving.

Korean Patent Publication No. 10-2008-0075638 "Tube Heating Structure of Urea SRC System" Korean Patent Publication No. 10-2006-0059400 "Urea aqueous solution freezing prevention structure using the exhaust gas of the engine" Korean Patent Publication No. 10-2007-0059641 "Diesel storage tank heating device of diesel engine" Registered Patent No. 0792927 "Urea Supply Device for SCR Post-Processing"

The present invention not only makes it easy to measure urea water level or control temperature, but also prevents urea water from freezing in winter or in cold weather.If urea water is frozen, it can be thawed quickly without the need to run the engine to stably supply urea water. It is an object of the present invention to provide a level sender unit dedicated to urea water tanks.

Particularly, in the present invention, a plurality of flexible straps having fluttering are attached to the inner wall surface of the cylindrical level sender unit mounted inside the urea water tank, and then have a plurality of flexible straps fluttering outside of the level sender unit. Since the urea water is heated immediately by drawing it out, the main purpose is to be able to quickly thaw the urea water without driving the engine in the early stage of cold start.

On the other hand, in the present invention by improving the structure and shape of the level sender unit and improve the shape of the urea tank to be coupled to this to make it easy to apply the urea water supply device to a passenger car with a relatively light vehicle weight and a small installation area For the purpose of

In order to achieve the above object, in the present invention, as mounted on the inside of the urea tank for the after-treatment of diesel engine exhaust gas of the SCR (SCR) method, the upper surface is opened, the hollow portion is formed inside the side A level sender body 102 through which a plurality of opening holes 101a penetrate along a circumference and a level sender head 102 for closing a bottom surface of the level sender main body; A hollow tube having an upper end closed and attached to a lead pipe 140 connected to a PCB board insertion hole 142 formed at the level sender head and an outer diameter of the lead pipe. A float 141 which slides to a side; A PCB substrate housing 143 which is inserted into the inner diameter of the lead pipe and has a PCB substrate for measuring the water level inside the urea water tank; A urea water suction side connector 111 and a urea water return side connector 121 whose one end extends to the inside of the level header main body and the other end extends to the outside of the level sender head; A filter 161 connected to the urea water suction-side connector extending into the level sender body and a filter housing 162 configured to receive and surround the filter; And a plate-shaped heating pad body 11 made of a rubber or insulating resin made of a flexible material and having a heating element embedded therein, and a plurality of straps 12 having a constant width as extending from one end of the heating pad body; A heating pad (10) formed of a power cable (14) electrically connected to the heating element and closely attached to an inner wall of the level sender main body (101); It proposes a urea water level sender unit comprising a.

Here, the strap of the heating pad is composed of the first strap 12a and the second strap 12b having different lengths up and down, and the first strap is passed through the opening hole 101a of the level sender main body, the level sender main body. It is preferable to install so as to be exposed to the outside of the.

An electric heating coil is mounted inside the level sender main body of the urea water suction side connector located inside the level sender main body, and a power cable connected to the heating element inside the heating pad is drawn out to the outside of the level sender head. do.

On the other hand, a plurality of reed switches are arranged on the PCB substrate, the magnet is embedded in the float.

According to another aspect of the present invention, the urea water level sender unit and the urea water level sender unit are mounted on the outside of the urea water tank main body 200 and urea water tank for storing urea water therein. Urea water storage and supply device characterized in that it comprises a pump 300 is attached to the urea water suction side connector 111 and the urea water return side connector 121 and the flow path of the urea water level sender unit Is also provided.

According to the present invention, the amount of urea in the urea tank and the temperature can be easily controlled to supply the urea water to the dosing unit in the required amount in a timely manner, and the urea water required without driving the engine even when the urea water is frozen in winter or cold season. It can be quickly thawed by a quantity and supplied to the dosing unit so that urea water is not supplied at the beginning of the cold start, thereby preventing the NOx component in the exhaust gas from being discharged into the air as it is.

In particular, in the present invention, after fixing a heating pad of a flexible material in which a heating element such as an electric heating coil or a planar heating element is internally fixed to the inner wall of the level sender unit contained in the urea water, a plurality of straps are swollen or urea water. It is possible to maximize the contact area between the heating pad and the urea water by configuring it to flutter at. Therefore, the thawing and heating of the urea water is quick and immediate even in the cold weather in winter.

In addition, the present invention has an advantage that the urea water level sender and the urea water tank in which the urea water level sender is mounted inside are small and have a simple structure, and thus can be easily applied to a passenger car having a small installation area. That is, the urea water storage and supply device including the urea water level sender unit of the present invention is cost-effective in that the heating of the urea water tank is not only fast and efficient, but also does not require a separate complicated heating device. It can be said that mounting convenience is excellent. In addition, the urea water storage and supply device of the present invention has the advantage that the structure is simple, so there is little risk of failure and very convenient installation and maintenance.

1 is an assembled perspective view of the urea water storage and supply apparatus of the present invention.
Figure 2 is a perspective view of the combined urea water tank and level sender of the present invention.
Figure 3 is an exploded perspective view of the urea water level sender of the present invention.
4 is a bottom view of the urea water level sender of the present invention;
Figure 5 is an external perspective view of the heating pad unfolded state of the present invention.
Figure 6 shows a conventional urea tube heating structure.
7 is a device configuration diagram of a urea water supply device according to another conventional example.

Hereinafter, with reference to the accompanying drawings, the configuration and operation principle of the present invention will be described in detail.

Figure 1 is an assembled perspective view of the urea water storage and supply apparatus of the present invention, showing a state actually installed in the rear trunk space, such as a passenger car.

The urea water storage and supply apparatus of the present invention is a level sender installed to be immersed in urea water by combining from a lower portion of the urea water tank 200, the urea water tank 200, which is a container for storing urea water in an interior volume thereof. A pump 300 which sucks urea water through the unit 100 and the level thunder unit 100 to supply or use a dosing unit (not shown) and provides hydraulic pressure for recovering the remaining urea water. It is composed.

Figure 2 is a combined perspective view of the urea water tank and the level sender of the present invention, for convenience of description is represented by flipping the bottom surface of the urea water tank 200 is visible.

The urea water tank 200 is a hollow container formed of synthetic resin such as polyethylene, and an urea water inlet 212 is formed on the upper surface to inject and replenish urea water, and a level sender unit 100 is inserted into the lower surface. As for mounting, a connecting end 202 is formed on the outer circumferential surface of the thread. In the figure, reference numeral 212a denotes an injection port plug. An air vent pipe 213 is provided on an upper surface of the urea water tank 200.

The urea water tank 200 has a fixing bracket 203 extending downward from the urea water tank body 201, and a plurality of fastening brackets 204 and 205 are formed on the side of the urea water tank body 201. To the vehicle body by bolts or the like. In the drawings, reference numerals 203a, 204a, and 205a indicate fastening holes, and 231, 232, and 233 of FIG. 1 indicate bolts, washers, and bushings, respectively, and constitute fastening means 230.

A drain pipe (211) is formed on the bottom of the urea water tank (200), and the pump (300) is fixedly mounted by the pump fixing bracket (206) and the fastening bolt (206a) at the front end. .

The pump 300 is for supplying urea water stored in the urea water tank 200 to a dosing unit (not shown), and includes a suction port 301, a return port 302, a discharge port 303, and the like. do. The suction port 301 is connected to the urea water suction side connector 111 of the level sender unit 100 to be described later by the suction side connector 221, and the return port 302 is the return side connector 222. Is connected to the urea water return side connector 121.

Figure 3 is an exploded perspective view of the urea water level sender of the present invention, Figure 4 is a bottom view of the urea water level sender of the present invention. 3 is shown upside down unlike the direction in which the actual level sender unit is mounted for convenience of description. Therefore, in the following description, in consideration of the direction in which the level sender unit 100 is actually installed, an upper side or a lower side and a lower side will be defined as an upper side or an upper side based on FIG. 3.

The level sender unit 100 includes a level sender main body 101 having a cylindrical shape having an upper surface open as a whole, and a level sender head 102 closing the bottom surface of the level sender main body 101. A plurality of open holes 101a are formed on the sidewall of the level sender main body 101 to penetrate the inside and the outside of the level sender main body.

The level sender head 102 has a urea water suction side connector 111, a urea water return side connector 121, a cable outlet end 131, a wire connection end 114, a PCB substrate housing insertion hole 142, and a temperature sensor. Insertion hole 154 is formed.

One end of the urea water suction side connector 111 is exposed to the inside of the level sender body 101 and the other end extends to the outside of the level sender head 102. Similarly, the urea water return side connector 121 extends from the inside of the level sender main body 101 to the outside of the level sender head 102.

The suction port 301 of the pump 300 is connected to the urea water suction side connector 111 by the suction side connector 221, and the urea water return side connector 121 is connected to the return side connector 222. By this, the return port 302 of the pump 300 is connected.

The suction side connector 221 and the return side connector 222 is preferably formed of a corrugated pipe or other well bent and flexible synthetic resin material for the convenience of connection.

Heat transfer means such as an electric heating coil is mounted near the portion of the urea water suction side connector 111 located inside the level sender main body 101. An electric wire cable 112 is connected to the heat transfer means, and is connected to a power source such as a battery of a vehicle. For drawing out the wire cable 112, as shown in FIG. 4, the wire connection end 114 is formed in the level sender head 102 and is closed by the suction side cap 113. As shown in FIG. Wire suction hole 113a is formed in the suction side stopper 113, and a sealing member (not shown) to prevent leakage of urea water at a coupling portion of the suction side stopper 113 and the wire connection end 114. ) Is mounted.

The coupling of the filter 161 and the filter housing 162 is connected to the urea water suction side connector 111 extending to the inside of the level sender body 101. The filter 161 is the same as the pleated paper filter to form a hollow cylindrical shape having a hollow portion 161b therein, but is not limited thereto. A filter connection end 161a is formed at a lower end of the filter 161 to connect to one end of the urea water suction side connector 111. In the drawings, reference numeral 161c denotes a seal for preventing leakage of urea water at the coupling portion.

The filter 161 is accommodated in the hollow cylindrical filter housing 162 having a hollow portion 162a therein, and a protrusion formed in the level sender head 102 at the lower end of the filter housing 162. Not shown) is formed with a coupling hole (162b) for fitting engagement.

The combination of the filter 161 and the filter housing 162 is mounted on the inner diameter side of the level sender unit 100 so as to be immersed in the urea water in the urea water tank 200. Therefore, the urea water is moved from the outside of the filter 161 to the inner hollow portion 161b through the inside of the filter housing 162 by the fluid transfer pressure of the pump 300, and then the urea water suction side connector 111 It is supplied to the outside of the urea water tank 200 through the other end.

As shown in the outer wall of the level sender unit 100, a lead pipe 140 of a hollow tube body is formed, and an upper end of the lead pipe 140 is closed to form a stopper 140a, and a lower end thereof is opened to level It is connected to the PCB housing insert 142 is formed through the sender head 102.

In the outer diameter of the lead pipe 140, a float 141 in which a magnet is embedded is mounted to be slidable up and down. The PCB substrate housing insertion hole 142 is inserted into the PCB substrate housing 143 containing a PCB substrate (not shown). The PCB substrate provided in the PCB housing 143 has a plurality of reed switches (not shown) arranged in a line in the length direction thereof so that two contacts are connected or dropped by a magnet of the float 141. The level of urea water is checked and measured.

A reed switch is a type of switch in which two contact portions are enclosed in a glass tube filled with an inert gas. When a current flows through a coil, the magnetic force lines pass through the lead made of a magnetic material, and thus, magnetic attraction force is generated and contacted. It is a kind of switch.

In the drawing, reference numeral 144 denotes a housing cap 144 for protecting the PCB board accommodated in the PCB housing 143, 144a indicates a wire through hole, and 145 indicates a wire for connecting the PCB board to a power source. Represent the cable.

The temperature sensor 150 is inserted into the temperature sensor insertion hole 154 of the level sender head 102 to measure the temperature of the urea water. The upper end of the temperature sensor 150 is equipped with a sealing 151 so as not to leak when combined with the temperature sensor insertion hole 154. In the drawing, reference numeral 152 denotes an electric wire cable for connection with an external power source.

The level sender head 102 is formed with a cable lead end 131 for the lead-out of the power cable 14 of the heating pad 10 to be described later, the lead end plug 132 is coupled thereto. A cable passage hole 132a for the heating pad power cable 14 is formed in the lead end plug 132.

5 is an external perspective view of the heating pad in the unfolded state of the present invention. Inside the level sender unit 100 of the present invention, a plate-shaped heating pad 10 as shown is mounted. Inside the heating pad 10, a heating element such as an electric heating coil or a planar heating element is embedded.

That is, the heating pad 10 is a flexible and flexible material of the heating pad body 11 made of a plate-like body of rubber or synthetic resin and a plurality of strands of straps 12 extending from one end of the heating pad body 11 Is done. The strap 12 is formed in a strip shape by cutting the heating pad body 11, which is a plate-shaped body, in a predetermined length and width, and may be formed of a first strap 12a and a second strap 12b according to its length. In the present embodiment, it is assumed that the first strap 12a and the second strap 12b are alternately formed.

In particular, the first strap 12a has a long strip shape, and a heating element is embedded therein, and as shown in FIG. 3, through the plurality of open holes 101a formed at the side of the level sender main body 101. It is withdrawn from the inside of the level sender main body 101 to the outside.

That is, since the heating pad 10 is formed of a flexible material, it is rolled in a cylindrical shape so as to be in close contact with the inner circumferential surface of the level sender main body 11, and then the first strap 12a is exposed through the opening hole 101a. It is to be made. In this way, the urea water inside and outside the level sender unit 100 immersed in the urea water tank 200 can be heated evenly. That is, in the case of the heating pad 10 of the present invention, the contact area with the urea water is increased, which is advantageous in preventing or freezing the urea water in the urea water tank 200.

One side of the heating pad 10 is formed with a power connection portion 13 which is a portion that is connected to the heating cable embedded in the power cable 14 and the heating pad body (11).

The present invention relates to a diesel exhaust after-treatment apparatus of the SRC method, can be easily installed inside the urea tank to control the temperature and water level, so that the urea water does not freeze in the cold weather in winter and quickly freeze the urea water once frozen It is to solve the problem that urea water is not supplied at the beginning of cold start by thawing.

Therefore, considering the future industrial environment in which environmental regulations on automobiles become more stringent, it will be necessary to apply widely to the after-sales system of small-sized vehicles such as diesel passenger cars as well as large diesel vehicles such as trucks and buses. .

10: heating pad 11: heating pad body
12: straps 12a, 12b: first and second straps
13: power connection 14: heating pad power cable
100: level sender unit 101: level sender main body
102: level sender head 111: urea water suction side connector
112: electric wire cable 113: suction side plug
121: number of elements return side connector 130: cable lead-out
132: lead end stopper 140: lead pipe
141: float 142: PCB housing housing opening
143: PCB substrate housing 144: housing cap
145: wire cable 150: temperature sensor
151: sealing 152: electric wire cable
161: filter 162: filter housing
171: Sealing 172: Level sender stopper 200: Urea water tank 201: Urea water tank body
202: connecting end 203: fixing bracket
204,205: fastening bracket 206: pump fixing bracket
221: suction side connector 222: return side connector
300: pump 301: suction port
302: return port 303: discharge port

Claims (5)

It is installed inside the urea tank for post-treatment of exhaust gas of SCR type diesel engine,
A level sender body 102 having an upper surface open, a hollow part formed therein, and closing the bottom surface of the level sender body 101 formed with a plurality of opening holes 101a passing through the side circumference;
A hollow tube having an upper end closed and attached to a lead pipe 140 connected to a PCB board insertion hole 142 formed at the level sender head and an outer diameter of the lead pipe. A float 141 which slides to a side;
A PCB substrate housing 143 which is inserted into the inner diameter of the lead pipe and has a PCB substrate for measuring the water level inside the urea water tank;
A urea water suction side connector 111 and a urea water return side connector 121 having one end extending to the inside of the level sender body and the other end extending to the outside of the level sender head;
A filter 161 connected to the urea water suction-side connector extending into the level sender body and a filter housing 162 configured to receive and surround the filter; And
A plate-shaped heating pad body 11 made of a rubber or insulating resin of a flexible material and having a heating element embedded therein, a plurality of straps 12 having a constant width as extending from one side end of the heating pad body, and A heating pad (10) formed of a power cable (14) electrically connected to a heating element and closely attached to an inner wall of the level sender body (101);
Urea water level sender unit characterized in that comprises a. The method of claim 1,
The strap of the heating pad is formed of a first strap 12a and a second strap 12b having different lengths up and down, and the first strap passes through the opening hole 101a of the level sender main body to the outside of the level sender main body. Urea water level sender unit characterized in that it is installed to be exposed to. The method of claim 2,
An electric heating coil is mounted inside the level sender main body of the urea water suction side connector located inside the main body, and a power cable connected to the heating element inside the heating pad is drawn out of the level sender head. Urea water level sensor unit. The method of claim 1,
A plurality of reed switches are arranged in the PCB substrate, the magnet is embedded in the float level level sender unit. A urea water level sender selected from any one of claims 1 to 4, wherein the urea water level sender unit is mounted, and a urea water tank main body 200 for storing urea water therein, and the urea water It is attached to the outside of the tank urea water characterized in that it comprises a pump 300 which is connected to the urea water suction side connector 111 and the urea water return side connector 121 and the flow path of the urea water level sender unit Storage and supply.

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