JP2006226282A - Piping unit of reducing agent tank and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous urea tank having a box-like body with small thermal distortion in which recesses are provided in the side face so as to improve pressure resistance and vibration resistance and to provide a piping unit which makes smooth the start of an engine by unfreezing aqueous urine in a short period of time and which can be mounted efficiently while reducing the number of steps of piping within the tank. <P>SOLUTION: The aqueous urea tank 10 includes the rectangular sheet-metal box-like body the front face of which is narrower in width than the side face. A plurality of recesses are formed in the side face. Both ends of the side face are joined to each other in the vicinity of the bending line of the side face, and at least one recess is arranged near the join line. In the piping unit of the aqueous urea tank 10, an aqueous urea temperature controlling pipe is arranged at the bottom of the tank and near the side face of a measuring pipe. A heat dissipation plate is provided at the periphery of a portion of the aqueous urea temperature controlling pipe locating at the bottom of the tank body, so that a suction port of an aqueous urea supplying pipe and the lower end of the measuring pipe are surrounded by the heat dissipation plate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a reducing agent tank piping unit used in an exhaust gas purification apparatus for automobiles and a method for manufacturing the same.

  2. Description of the Related Art Conventionally, in a diesel engine exhaust gas purification device, a type of purification device that sprays urea water as a reducing agent on the inlet side of a NOx reduction catalyst arrangement portion of an exhaust pipe has been developed. In this purification device, exhaust gas from the engine is produced from urea water or urea water as a reducing agent in the inlet side or inlet side pipe of the NOx reduction catalyst housed in the NOx catalytic converter incorporated in the middle of the exhaust pipe. Ammonia gas is injected, NOx is selectively reduced, and finally decomposed into nitrogen gas and water (Patent Documents 1 to 6).

  The details of the purification devices that work in this way are also different for each company, and each company has its own traces of ingenuity. For example, with regard to the supply and retention of urea water, if there is one (Patent Document 2) in which urea powder is supplied to a urea water tank and the urea powder is stirred and mixed with water, the fuel is supplied from a supply source such as a gas station. There is also a type in which urea water is replenished to a urea water tank arranged on the side of the tank (Patent Document 3). In addition, if there is one (Patent Documents 1 and 6) that supplies urea water with temperature control within an appropriate temperature range by a heater provided in a urea water tank or supply pipe, ammonia gas is generated from the urea water to produce ammonia. Some are stored in a gas tank and the ammonia gas is supplied into the exhaust pipe (Patent Document 4), and a plurality of catalysts are used, urea water or aqueous ammonia solution or liquid ammonia just before the selective catalytic reduction catalyst. There is also one that is supplied by spraying (Patent Document 5).

Japanese Patent Laid-Open No. 2000-027627 JP 2002-166130 A JP2003-278532A JP 2004-108185 A JP 2004-218475 A Japanese Patent Laid-Open No. 2004-270609

[Problems of the prior art]
In conventional urea water tanks used for exhaust gas purification devices for diesel engines, the tank specifications are individually designed and manufactured according to the vehicle used, so it is designed for many vehicles of many companies. Various types of urea water tanks will be designed, and it is required to manufacture various types of urea water tanks. And in order to make it respond | correspond to various specifications, since the influence of the apparatus provided outside becomes large and the number and the position of the piping to be attached differ, the manufacture kind of a tank increases further.

  The body of the urea water tank is required to be as narrow as possible due to the limitation of installation space on the vehicle. In addition, urea water is not corrosive, but ammonia produced by hydrolysis has strong corrosivity, and therefore, stainless steel is used as a tank material in consideration of corrosion resistance. For this reason, the linear expansion coefficient is 1.5 times higher than that of ordinary structural steel, and is easily affected by heat due to welding.

  Also, in cold districts, when the outside air temperature falls below the freezing point of urea water (liquid reducing agent), urea water may freeze, and it takes time to thaw urea water to start the engine. The time will be longer. For this reason, in order to start the engine quickly and smoothly, urea water is supplied into the tank, the air is extracted when the urea water is supplied, the urea water is warmed and thawed, and the thawed urea water is removed. A urea water system pipe that sucks in and returns excess urea water and a measurement system pipe that checks the state of the urea water, such as a water level sensor and a concentration sensor, must be provided in the tank. However, disposing various types of pipes with good workability is a difficult and time-consuming work that is unexpected in practice, and increases man-hours.

  The present invention has been made in view of the above-mentioned problems in the prior art, and the problems specifically set in order to solve this problem include reducing agents around the reducing agent supply pipe, the concentration meter, and the water level meter. An object of the present invention is to provide a reducing agent tank piping unit and a method for manufacturing the same, which can be thawed in a short time so that the engine can be started quickly and smoothly, and the number of man-hours for piping in the tank can be reduced.

In order to identify the reducing agent tank piping unit and the manufacturing method thereof in which the above-mentioned problems in the present invention are effectively solved, all the matters recognized as necessary are specifically covered, and the problem-solving means is specifically configured. Is shown below.
The first problem solving means relating to the reducing agent tank piping unit is that, in the reducing agent tank piping unit, the heat transfer member serving as the upper surface plate includes a grommet hole drilled at a predetermined interval through which each measurement pipe passes. And a grommet that is fitted in the grommet hole and is provided so that the measurement pipe can be inserted and removed.

  The second problem-solving means relating to the piping unit of the reducing agent tank is characterized in that the heat transfer member serving as the side plate is formed by bending the edge located on the upper side inward to form a rectangular flat portion. .

  A first problem-solving means relating to a method for manufacturing a reducing agent tank piping unit is the method for manufacturing a reducing agent tank piping unit, wherein an upper surface plate is fixed to the bottom of the reducing agent temperature management piping, and the planar shape is After arranging two side plates formed in an L shape along the pipe shape, the top plate and the side plate are temporarily fixed to the bottom of the reducing agent temperature control pipe by welding, and then the reduction is performed. Insert the agent supply pipe inside the side plate and temporarily fix the reducing agent supply pipe and the reducing agent temperature control pipe by welding at appropriate locations, A curved surface portion is disposed along the bottom of the reducing agent temperature management pipe and temporarily fixed by welding, and then brazed in a furnace, and the upper surface plate is attached to the end of the reducing agent temperature management pipe on the tank bottom side. The side plate and the bottom plate are integrated. It is characterized in that the fixation was.

  The second problem solving means relating to the manufacturing method of the piping unit of the reducing agent tank is to set the bottom of the reducing agent temperature management piping on a jig to determine the upper and lower positions, and to the piping set in the jig, the upper surface plate Then, two side plates having the L-shaped planar shape formed on the side surface on the bottom side of the reducing agent temperature management pipe are arranged along the pipe shape to reduce the reducing agent temperature management pipe. The bottom part of this is pressed from the side, and a predetermined position is temporarily fixed by welding.

  The third problem solving means according to the method of manufacturing the piping unit of the reducing agent tank is to insert the reducing agent supply pipe into the inside surrounded by the side plate from the corner of the top plate, and to supply the reducing agent. The lower end of the pipe is disposed inside the pipe located on the tank bottom side of the reducing agent temperature management pipe, and the reducing agent supply pipe and the reducing agent temperature management pipe are temporarily fixed by welding at appropriate locations. It is characterized by that.

  A fourth problem-solving means relating to the manufacturing method of the reducing agent tank piping unit is that an upper surface plate and a side plate are assembled in the vicinity of the tank bottom portion of the reducing agent temperature management piping and the reducing agent supply piping. Remove the temporarily fixed product pressed from the side from the jig, and arrange the curved surface portion of the bottom plate along the bottom of the reducing agent temperature management pipe and the reducing agent suction pipe of the reducing agent supply pipe and the It arrange | positions so that the position with the hole drilled in the bottom face plate may match, and is temporarily fixed by welding.

  A fifth problem solving means relating to a manufacturing method of a piping unit of a reducing agent tank is that after the piping unit is brazed, a reducing agent suction port of the reducing agent supply pipe is provided through a hole formed in the bottom plate. A reducing agent suction port sealing mech plug is inserted into the reducing agent supply pipe and an air tightness test is performed. After the reducing agent suction port sealing mech plug is inserted into the bottom plate through the hole formed in the bottom plate. The reducing agent supply pipe is extracted so that the reducing agent can be sucked, and then a blind plate is welded and closed in a hole formed in the bottom plate.

  In the present invention, in the first problem solving means relating to the piping unit of the reducing agent tank, the grommet is fitted into the grommet hole of the top plate, and the leading end of each measurement pipe is inserted to penetrate the top plate. Each measurement pipe is inserted inside a thin plate heat transfer section made of thin plate material, and it is possible to secure a seal between each measurement pipe and the grommet hole. Even if the distance from the lid panel attachment point to the upper surface plate is long, it can absorb the misalignment between the center of the insertion hole on the lid panel side and the center of the insertion hole on the upper surface plate, and does not freeze or thaw when supplying the reducing agent. The reduced reducing agent can be sucked, and the state of the reducing agent at the time of suction can always be measured.

  In the second problem-solving means relating to the piping unit of the reducing agent tank, it can be easily positioned by placing the upper surface plate on the flat portion formed on the side surface plate, and then easily assembled by temporarily welding. it can.

  In the first problem solving means relating to the manufacturing method of the piping unit of the reducing agent tank, the top plate and the side plate are temporarily fixed to the end portion on the tank bottom side of the reducing agent temperature management piping first, and then the bottom plate is attached. By brazing in the furnace after temporarily fixing, it is easy to position the pipes, and a production process with good mass productivity can be configured, thereby reducing the cost.

  In the second problem solving means relating to the manufacturing method of the piping unit of the reducing agent tank, the reducing agent temperature management pipe is erected by using a jig to determine the vertical position, and subsequently the lower end of the reducing agent temperature management pipe A side plate is arranged on the side surface of the pipe along an L-shaped bent portion on the outer peripheral surface of the pipe, and a jig is used to fix the position by pressing the lower end portion of the reducing agent temperature management pipe and the side plate provided on the outer periphery thereof. In addition, the variation in assembly dimensions can be reduced, and the assembly dimensions can be maintained with high accuracy even if the subsequent temporary welding or the like is performed.

  In the third problem solving means relating to the manufacturing method of the reducing agent tank piping unit, the reducing agent supply pipe is disposed in the immediate vicinity of the reducing agent temperature management pipe, and the reducing agent suction port is enclosed by a thin heat transfer member. It is installed inside the thin plate heat transfer section, and it can be kept warm until the reducing agent is sucked from the carbon water suction port by the heat from the reducing agent temperature control pipe and goes out of the tank, without freezing the reducing agent Can be supplied.

  In the fourth problem-solving means relating to the manufacturing method of the piping unit of the reducing agent tank, the bottom plate is specified and assembled according to the bending of the reducing agent temperature management piping and the position of the reducing agent suction port of the reducing agent supply piping. As a result, the bottom plate can be assembled with high accuracy and work efficiency, and the airtight inspection in the subsequent process can also improve the work efficiency, facilitating the production of the thin plate heat transfer section and improving the work efficiency during production. The manufacturing cost can be effectively reduced.

  In the fifth problem solving means relating to the manufacturing method of the piping unit of the reducing agent tank, even if an airtight test is incorporated in the middle of the manufacturing process, the manufacturing process can proceed without dismantling work in the middle, and the manufacturing efficiency is reduced. The airtight test can be carried out without doing so.

Hereinafter, the best embodiment of the present invention will be specifically illustrated and described with respect to the case of using urea water as a reducing agent.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the content of the invention unless otherwise specified.
That is, in the following embodiments, the reducing agent to be used is urea water, but other reducing agents such as an aqueous ammonia solution or liquid ammonia are also applicable.

〔Constitution〕
As shown in FIGS. 1 to 3, the urea water tank 10 in this embodiment is a sheet metal box, and the size of the side surface is substantially the same as the size of the side cross section of the fuel tank so that it can be disposed on the side of the fuel tank. The inlet 10 is formed in a rectangular parallelepiped with a width corresponding to the required volume, and the upper part of the front face 10a is penetrated by the cylindrical member 11a. (See FIG. 6), and a pipe assembly 13 unitized as a pipe assembly member is attached to the lid panel 12 to be attached to the opening 10c. The pipe assembly 13 opens various pipes provided through the lid panel 12. 10c, the upper ends of the various pipes are projected above the lid panel 12, and the main parts of the various pipes are projected below the lid panel 12, To facilitate attachment work of the urea water tank 10 as well as to facilitate connection of the piping.

  As shown in FIGS. 2 to 4, the pipe assembly 13 includes an identification sensor (provided with an identification sensor protection pipe 14 a (see FIG. 8)) that checks whether the concentration of urea water in the tank is maintained at a prescribed level. Concentration meter) 14, water level sensor pipe 15 a (see FIG. 8), and a water level sensor (water level meter) 15 for checking whether the water level of urea water is within a specified range, urea water temperature management pipe 16 a (see FIG. 8) A thawing and heat retaining system 16 for heating urea water by the heat of the pipe fluid, and a urea water supply pipe 17a, a urea water return pipe connection part 17b, an air vent pipe 17c, and an upper end part of the air vent pipe 17c. There is a urea water system pipe 17 provided with a hose 17d (see FIG. 3) that discharges the overflowed urea water to the outside.

As shown in FIGS. 3 to 6, the main body forming the sheet metal box of the urea water tank 10 is provided with an opening 10 c for inserting the pipe assembly 13 on the upper surface 10 b of the urea water tank 10. After the thick part 10d is formed around 10c and the pipe assembly 13 is assembled, the lid panel 12 can be detachably fixed to the thick part 10d via the packing 18.
In addition, a drain hole 10e is provided on the lower surface, a nut or a bolt having a hole formed concentrically at the center is welded, and a bolt or a cap nut is screwed into the spot as a blind cover 19 via a packing, By removing the blind lid 19, the liquid can be drained.

  Further, the side surface plate 10f of the urea water tank 10 has a shallow depth, a wide width, and a vertically long shape at a position where the middle portion of the baffle plate placement position is divided into approximately three equal parts in a vertical row. Recesses 10g,..., 10g formed to be recessed toward the inner surface side are provided, and unevenness is formed on the side plate 10f to increase rigidity.

Inside the urea water tank 10, baffle plates 20, 20 with round holes 20 a, 20 a drilled in the upper and lower positions in the center are arranged so that the side ends 20 b, 20 b bent in the same direction face each other. Then, the side edge is welded and fixed to the side plate 10f.
Outside the urea water tank 10, a level gauge 10h for confirming the amount of liquid that is long in the vertical direction is provided at the upper end on the front side of the side plate 10f, and in the lateral direction on the upper end on the back side of the plate member that forms the upper surface 10b. An extending handle 10i is provided to facilitate handling of the tank when performing attachment and removal operations.

  As shown in FIGS. 7 to 10, the pipe assembly 13 is formed by unitizing the identification sensor 14, the water level sensor 15, the thawing and heat retaining system 16, the urea water system piping 17, etc., and penetrates the lid panel 12. Each pipe 14a, 15a, 16a, 17a hanging downward is surrounded by a thin plate material 41 serving as a heat transfer plate at the lower end of the urea water temperature management pipe 16a so that the pipes are formed by a heat transfer section 43 formed in a box shape. Integrate the lower part.

  The shape of the urea water temperature management pipe 16a is suspended while adjusting the position from the pipe connection portion provided on the lid panel 12 to a predetermined position, and is bent so as to be horizontal in the tank depth direction at the lowest position. Bend upward in the vertical direction, stand up, fold in the tank thickness direction at a predetermined height, fold down again at the position where the pipes are lined up with a predetermined width, and hang down to the same height as the rising position, and horizontally at that position It is bent to the direction return side, then bent upward in the vertical direction, rises, and is formed in a shape to be connected by adjusting the position so as to be connected to the return side pipe connection portion provided on the lid panel 12. Among these, at the upper end raised to a predetermined height bent in the thickness direction of the tank, the outer surface of the pipe is brought into contact with and fixed to the plate-like support member 12a suspended from the lower surface of the lid panel 12 to the pipe connection side. Support the opposite end to prevent unnecessary movement.

As shown in FIGS. 10 to 12, the thin plate material 41 brazes the side plates 41 a, 41 a, 41 b, 41 b and the bottom plate 41 c to the urea water temperature management pipe 16 a and uses it as a heat radiating plate.
The upper surface plate 41d is provided with arc-shaped cutouts 41m,..., 41m (see FIG. 21) that fit into the urea water temperature management pipe 16a at four corners, and two grommet holes 41i are formed at predetermined intervals in the longitudinal direction. In addition to being used as a heat transfer plate, it is also used as a pipe positioning member for positioning the pipes 14a and 15a via grommets 42 and 42 fitted in the two grommet holes 41i, respectively.

  The bottom plate 41c is easily positioned by bending one end thereof in accordance with the curvature of the pipe, leaving the other end flat, and placing the curved surface portion 41n along the curve of the urea water temperature management pipe 16a. And a size that allows a mesa plug (not shown) for fitting to the suction port to pass through the position of the plane portion corresponding to the urea water suction port 17e of the urea water supply pipe 17a. Holes 41j (mecula plug passage holes), and after brazing, the mecula plugs are inserted into the urea water suction port 17e of the urea water supply pipe 17a through the holes 41j, and the urea water supply pipe 17a It will be possible to perform airtight inspection.

  The side plate 41a on the short side and the side plate 41b on the long side have a width of 90 mm so as to have a length obtained by matching one plate material with sides having different lengths, as shown in FIGS. ° Bend, the upper end is bent 90 ° inward leaving both ends of the side plates 41a and 41b, and a linear flange is formed as the flat portions 41k and 41l for placing the upper plate, thereby integrating the heater Formed on plates 45 and 45.

  Further, as shown in FIG. 11, the urea water temperature management pipe 16a and the urea water supply pipe 17a are not only near the lid panel 12 but also in the upper part of the tank by brazing the small thin plates 41e, 41f, 41g. Take care not to freeze. In addition, before brazing the small thin plate members 41e, 41f, 41g, in order to temporarily fix the urea water temperature management pipe 16a and the urea water supply pipe 17a, the lower side of the brazing position of the small thin plate member 41g A small thin plate material 41h is welded to the straight portion located at the position.

The pipes 16a, 17a hanging down from the lid panel 12 of the thawing and heat retaining system 16 and the urea water system pipe 17 braze the straight part in the middle of the drooping. The urea water temperature management pipe 16a is a thawing heater pipe, and the urea water supply pipe 17a is a urea water supply pipe that sucks urea water in the tank.
Since the two pipes 16a and 17a are integrated by brazing, the heat from the urea water temperature management pipe 16a is efficiently transmitted to the urea water supply pipe 17a to accelerate the thawing of the urea water and at a predetermined temperature. The temperature is raised to a temperature so that urea water can be sucked and supplied uniformly.

  The pipes 14a and 15a hanging downward from the flanges of the identification sensor 14 and the water level sensor 15 are in direct contact with the respective parts of the thin plate material 41 including the side plates 41a, 41a, 41b and 41b, the top plate 41d and the bottom plate 41c. In order to avoid this, positioning is performed via rubber grommets 42 and 42 fitted into the upper surface plate 41d (see FIGS. 7 and 8).

  As shown in FIGS. 10, 15, and 16, the grommet 42 is formed so that the outer peripheral surface 42a and the inner peripheral surface 42b are concentric, and the outer peripheral surface 42a has a grommet hole 41i formed in the upper surface plate 41d. The fitting groove 42c to be fitted is engraved as a narrow groove deepened from the outer peripheral surface 42a toward the center, and the end portion on the inner peripheral side has an inverted conical surface whose diameter is reduced as the upper surface is lowered toward the lower surface side. Forming a tip 42d on the small diameter side so that the thickness becomes substantially constant by curving in the direction of increasing the diameter as it goes further downward from the position of the minimum diameter (formation position of the inner peripheral surface 42b) From the above, it is easy to penetrate or pull out the cylindrical pipe.

  As a general rule, the urea water tank 10 including the pipe assembly 13 is made of stainless steel as a material to be used, and nickel brazing is used for brazing between pipes or brazing between a thin plate material and a small thin plate material. The grommet 42 is made of ethylene propylene rubber (EPR) or ethylene propylene diene monomer (EPDM). Of these, EPDM is more preferably used.

[Manufacturing]
To manufacture the pipe assembly 13, first, a jig is prepared.
As shown in FIGS. 17 and 18, the jig 51 includes a frame body 52 formed of columns 52 c,..., 52 c between the top plate 52 a and the bottom plate 52 b, and a column 52 c, between the top plate 52 a and the bottom plate 52 b. 52c, a small ceiling / floor / support structure comprising a flat upper support plate 53 and a lower support plate 54, which are provided so as to be movable up and down.

The upper support plate 53 has an opening (not shown) having the same size as the opening 10c provided on the upper surface of the urea water tank 10, and a long side clamp 55a for fixing the lid panel 12 to the periphery of the opening. Then, a lid panel holding member 55 comprising a short side clamp 55b is disposed.
In order to externally fit the grommet holes of the back side block 56a, the side block 56b, the pipe support blocks 56c and 56c, and the top plate 41d for determining the arrangement position of the urea water temperature management pipe 16a. A support block 56 comprising upper plate support blocks 56d, 56d having a cross-sectional shape of a half-moon is disposed.
Further, a manual equipped with a holding plate 57a for suppressing the side plate 41a on the short side so that the support block 56 and the side plate 41a on the short side or the side plate 41b on the long side can be pressed independently. The pneumatic clamp 58 having a large holding plate 58a for holding the side plate 41b on the long side is disposed at the end opposite to the position on the back side block 56a and the pneumatic clamp 58 provided with the side block 56b. It is placed on the opposite end.

In order to assemble the pipe assembly 13 to the jig 51, first, the lid panel 12 is set to a predetermined position on the upper support plate 53, and the long side clamp 55a and the short side clamp 55b are moved to the tightening side. Fix it.
An end portion of the urea water temperature management pipe 16 a formed in a predetermined shape is connected to the urea water temperature management pipe connection portion of the fixed lid panel 12, and is attached to the lower support plate 54 of the jig 51. The lowermost end of the urea water temperature management pipe 16a is placed on the step portions formed on both sides of the pipe support blocks 56c, 56c, and the pipe hanging from the lid panel 12 is brought into contact with the back side block 56a. At the same time, the return side tube is brought into contact with the side block 56b, the upper end portion on the return side is brought into contact with the support member 12a suspended from the lid panel 12, and the holding plate 57a of the manual clamp 57 is further positioned. The holding plate 58a of the pneumatic clamp 58 is moved in a direction to contact the side plates 41a and 41b, respectively, and pressed to fix the position.

Next, as shown in FIGS. 19 and 20, heater plates 45 and 45, in which side plates 41a and 41b are integrated, are inserted between each block 56a and 56b and the urea water temperature management pipe 16a. The two heater plates 45, 45 surround the side surface of the portion disposed at the lower end of the tank of the urea water temperature management pipe 16a, and the sides of the heater plates 45, 45 that are not sandwiched between the blocks and the pipes By respectively moving the holding plates 57a and 58a in the pressing direction by manual operation or pneumatic operation, the heater plates 45 and 45 are pressed and positioned on the urea water temperature management pipe 16a side.
After positioning, an appropriate location is temporarily fixed by spot welding between the urea water temperature management pipe 16a and the heater plate 45.

  Thereafter, the upper end of the urea water supply pipe 17a formed in a predetermined shape is set in the urea water supply pipe connection portion of the lid panel 12, and the urea water temperature management pipe 16a and the heater plate are connected to the lower pipe of the panel. 45, and the lower end portion is arranged inside the arrangement position on the lower end side of the urea water temperature management pipe 16a so that the urea water temperature management pipe 16a and the urea water supply pipe 17a are connected to each other. Is fixed by temporarily fixing an appropriate position by spot welding.

  After temporarily fixing the heater plate 45, that is, the side plates 41a and 41b and the urea water supply pipe 17a, the grommet holes 41i and 41i of the upper plate 41d are inserted into the upper plate support blocks 56d and 56d as shown in FIG. At the same time, the upper surface plate 41d is placed on the flat portions 41k and 41l formed on the heater plates 45 and 45, and the upper surface plate 41d is temporarily fixed to the heater plate 45 by spot welding to fix the position.

After temporarily fixing the upper surface plate, the heater plates 45, 45, the upper surface plate 41d, the urea water temperature management pipe 16a, and the urea water supply pipe 17a are removed from the jig 51, and as shown in FIG. The bottom plate 41c is placed along the shape of the lower end (bottom surface) of the urea water temperature management pipe 16a with the bottom surface of the heater plate temporary fixing portion turned upside down, and the urea water suction port of the urea water supply pipe 17a 17e and the hole 41j drilled in the bottom plate 41c are arranged and positioned so that they are aligned with each other and temporarily fixed at an appropriate position by spot welding.
Then, a brazing material is applied so that the contact portions between the pipes, the heater plates 45 and 45, the upper surface plate 41d, and the bottom surface plate 41c can be filled with nickel brazing, and are integrally brazed in a vacuum furnace. The heat transfer part 43 formed in a box shape using the thin plate material 41 is integrally formed at the lower end of the urea water temperature management pipe 16a (see FIG. 12).

After brazing each pipe to the thin plate material, a mesa plug is inserted into the urea water suction port 17e of the urea water supply pipe 17a through the hole 41j so that the airtight test of the urea water supply pipe 17a can be performed. Inspect by an airtight test, and confirm that the welded temporary brazing and brazing are performed as prescribed, and the pipe has no through-scratches.
Further, one end of the urea water temperature management pipe 16a is closed, pressure is applied from the other end, an airtight test of the urea water temperature management pipe 16a is performed, and welding temporary brazing and brazing are performed as prescribed. Inspect and confirm that the pipe has no flaws penetrating it.
After completion of the airtightness test after brazing, after removing the plug from the suction port of the urea water supply pipe 17a and removing the plug through the hole 41j, the bottom plate 41c is drilled as shown in FIG. The hole 41j is sealed by spot welding a disc-shaped blind plate 44 to the hole 41j.

  After the side plates 41a and 41b, the top plate 41d, and the bottom plate 41c of the thin plate material 41 are formed in a box shape, and the heat transfer portion 43 surrounding the lower end portion of the urea water temperature management pipe 16a is formed. The upper and lower sides are returned to the original position, the lid panel 12 is turned upward, the heat radiation portion forming side is turned downward, and the same direction as in the use state is set. Then, as shown in FIG. 24, the grommets 42 and 42 are fitted into the respective grommet holes 41i and 41i formed in the upper surface plate 41d, and the distal ends of the identification sensor protection pipe 14a and the water level sensor pipe 15a are covered with the lid. The pipe 12 is inserted from the side of the panel 12 through the grommet 42 fitted into the upper surface plate 41 d, and each pipe tip is inserted into the heat transfer section 43.

  The grommet 42 forms an inverted conical surface whose diameter is reduced as the central portion is lowered from the upper surface toward the lower surface side, and the diameter is increased as the diameter is further lowered from the minimum diameter position (formation position of the inner peripheral surface 42b). Since the distal end portion 42d on the small diameter side is formed so that the thickness is substantially constant, and the cylindrical pipe is easily penetrated or pulled out from above, the identification sensor protection pipe 14a and The water level sensor pipe 15a can be easily inserted and removed, and can be easily assembled to the heat transfer section 43.

[Function and effect]
Thus, by attaching the pipe assembly 13 as a unit to the lid panel 12, the lower part of the pipe assembly 13 is inserted into the opening 10c formed on the upper surface of the tank, and the thick portion 10d formed around the opening 10c. When the lid panel 12 is fixed using fastening parts such as screws or bolts, the respective pipes are arranged at predetermined positions and the urea water tank 10 is assembled.
For this reason, the urea water tank 10 can be assembled only by attaching the lid panel 12 to which the pipe assembly 13 is attached to the opening 10c from the upper surface of the tank. Compared to the conventional manufacturing method in which the pipes are individually attached, Workability is improved and productivity is improved.

The urea water temperature management pipe 16a and the urea water supply pipe 17a are brazed, heat is transferred from the urea water temperature management pipe 16a to the urea water supply pipe 17a, and the temperature of the urea water supply pipe 17a is increased. In addition, by warming the surrounding urea water, it is possible to smoothly supply the urea water, and it is possible to prevent the urea water supply from being hindered or inhomogeneous due to freezing or increased viscosity at low temperatures. Like that.
In addition, the urea water temperature management pipe 16a and the urea water supply pipe 17a are brazed to the small thin plate members 41e, 41f, and 41g even in the vicinity immediately below the lid panel 12 to enhance heat transfer between the pipes even in the upper part of the tank. Since the urea water is prevented from freezing by dissipating heat to the urea water around the pipe, it is possible to ensure the suction supply of the urea water.

By attaching a thin plate material serving as a heat transfer plate to a portion of the urea water temperature management pipe 16a disposed at the bottom of the tank and surrounding the lower end portion of the pipe assembly 13 with the thin plate material, the pipes can be integrated together. In addition, the vicinity of the urea water suction port 17e can be warmed to prevent the urea water from freezing, the urea water can be sucked without any trouble, and the surroundings of each sensor can be kept warm to increase the reliability of measurement. Can be improved.
The lower end portions of the identification sensor protection pipe 14a and the water level sensor pipe 15a can be removably fitted into the upper surface plate 41d via the grommet 42, so that the position can be easily fixed and the thin plate material 41 and the pipes 14a and 15a can be fixed. Can be prevented from coming into direct contact with each other, and can be prevented from coming into contact with each other as well as being steady, thereby improving the durability of the measuring apparatus and the reliability of the measurement.

  In the pipe assembly 13, various pipes such as a urea water temperature management pipe 16 a, a urea water supply pipe 17 a, an identification sensor protection pipe 14 a, and a water level sensor pipe 15 a are fixed together on the lid panel 12. By simply attaching the lid panel 12 to the upper surface, the piping in the tank can be efficiently piped at a predetermined position, and the surroundings of the urea water suction port 17e, the concentration meter and the detection unit of the water level meter are surrounded by the heat transfer unit 43. As a result, the heat from the urea water temperature management pipe 16a is confined in the heat transfer section 43, and urea in the heat transfer section 43 (around the urea water suction port 17e, the concentration meter and the water level detector detection section). The water can be efficiently thawed and the function as an exhaust emission control device can be exhibited in a short time after the engine is started.

Further, in the pipe assembly 13, heat from the urea water temperature management pipe 16a is transmitted to the urea water supply pipe 17a via the small thin plate members 41e to 41h, and the urea water can be supplied without freezing.
Further, in the pipe assembly 13, the top plate 41 d formed from the thin plate material 41, the bottom plate 41 c, the short side plate 41 a and the long side plate 41 b are integrally formed into an L-shaped planar shape. The two heater plates 45 and 45 were used, the two heater plates 45 and 45 were attached first, and then the top plate 41d and the bottom plate 41c were attached in order to form the heat transfer section 43, thereby forming a thin plate material 41 can be easily assembled in a box shape.
In the pipe assembly 13, the tip of each measurement pipe is inserted into the grommet 42 fitted in each of the grommet holes 41 i, 41 i of the upper surface plate 41 d, thereby passing through the upper surface plate 41 d and transmitting the thin plate material 41. Each measurement pipe is inserted inside the heat section 43, and when supplying urea water, the urea water that is not frozen can always be sucked and the state of urea water at the time of suction is measured and monitored. be able to.

It is a perspective view which shows the urea water tank in embodiment of this invention. It is a front view which shows a urea water tank same as the above. It is a side view which shows a urea water tank same as the above. It is a top view which shows a urea water tank same as the above. It is an expanded sectional view of the A section in FIG. It is a top view which shows a urea water tank main body same as the above. It is a front view which shows the pipe assembly of a urea water tank same as the above. It is a side view which shows the pipe assembly of a urea water tank same as the above. It is a top view which shows the pipe assembly of a urea water tank same as the above. It is an expanded sectional explanatory view shown by the FF line in FIG. It is an expansion perspective view which shows the small thin board | plate material brazed to piping located in the tank upper part of the pipe assembly of a urea water tank same as the above. It is an expansion perspective view which shows the thin plate material brazed to the lower end part of the pipe assembly of a urea water tank same as the above. It is an expansion perspective view which shows the side plate of a thin plate material same as the above. It is an expansion perspective view which shows the other side board of a thin board material same as the above. It is a longitudinal cross-sectional view which shows the grommet used for the pipe assembly of a urea water tank same as the above. It is a bottom view which shows the grommet used for the pipe assembly of a urea water tank same as the above. It is side explanatory drawing which shows the state which set the piping for urea water temperature management to the piping support jig used for manufacture of a pipe assembly same as the above. It is an A arrow directional view (plan view) in FIG. 18 which shows the state before setting a side plate in manufacture of a pipe assembly same as the above. It is side explanatory drawing which shows the state which set the piping for urea water supply to the piping support jig used for manufacture of a pipe assembly same as the above. It is an A arrow directional view (plan view) in FIG. 19 which shows the state which set the side plate in manufacture of a pipe assembly same as the above with operation of a jig. It is plane explanatory drawing which shows the operation | work which sets an upper surface board in manufacture of a pipe assembly same as the above. It is an isometric view explanatory drawing which shows the operation | work which sets a bottom plate in manufacture of a pipe assembly same as the above. It is a perspective explanatory view which shows the state which fixes a cap to a bottom plate same as the above. It is explanatory drawing which shows the state which inserts and sets the pipe for water level sensors in a grommet in manufacture of a pipe assembly same as the above, (A) is a fragmentary sectional side view which shows the state before setting, (B) is a part which shows a set state It is a cross-sectional side view.

Explanation of symbols

10 Urea water tank (reducing agent tank)
10a Front 10b Top 10c Opening 10d Thick part 10e Drain hole 10f Side plate 10g Recess 10h (For liquid volume confirmation) Level gauge 11 Inlet 11a Cylindrical member 12 Lid panel 12a (Pure for urea water temperature management) Support member 13 Pipe assembly (Piping assembly members)
14 Identification sensor 14a Identification sensor protection piping 15 Water level sensor 15a Water level sensor piping 16 Defrosting and heat retention system 16a Urea water temperature management piping (reducing agent temperature management piping)
17 Urea water piping (reducing agent piping)
17a Urea water supply piping (reducing agent supply piping)
17b Urea water return piping connection (reducing agent return piping connection)
17c Air venting pipe 17d Hose 17e Urea water suction port (reducing agent suction port)
18 Packing 19 Blind lid 20 Baffle plate 20a Round hole 20b Side end 41 Thin plate (heat sink)
41a, 41b Side plate 41c Bottom plate 41d Top plate 41e, 41f, 41g, 41h Small thin plate material 41i Grommet hole 41j Hole (hole for passing through a plug)
41k, 41l (for mounting the upper surface plate) flat surface portion 41m (arc-shaped) notch 41n curved surface portion 42 grommet 42a outer peripheral surface 42b inner peripheral surface 42c fitting groove 42d (on the small diameter side) distal end portion 43 heat transfer portion 44 blind Plate 45 Heater plate 51 Jig 52 Frame 52a Top plate 52b Bottom plate 52c Support column 53 Upper support plate 54 Lower support plate 55 Lid panel restraint 55a Long side clamp 55b Short side clamp 56 Support block 56a Back side block 56b Side block 56c Piping support block 56d Top plate support block 57 Manual clamp 57a Holding plate 58 Pneumatic clamp 58a Holding plate

Claims (9)

The tank body is a rectangular parallelepiped sheet metal box with a narrow front,
A urea water tank characterized in that a plurality of vertically long concave portions are provided on a side surface, both end portions are joined in the vicinity of the folding line of the side surface, and at least one concave portion is arranged in the vicinity of the joining line.   2. The urea water tank according to claim 1, wherein each baffle plate is disposed on the inner surface side of the tank main body at a position closer to the end of the tank than the respective recesses.   The tank body is provided with an inlet projecting upwardly on the front surface, and a collar part is provided on the outer periphery of the cylindrical member of the inlet, and a tongue projecting from the collar part is fitted to the lid fitted to the opening end of the cylindrical member. The urea water tank according to claim 1, wherein a tongue piece engaging groove into which the piece is inserted is formed. A pipe assembly member comprising a lid panel detachably attached to the upper surface of the tank body, a urea water supply pipe, a urea water temperature management pipe, various measurement pipes and an air vent pipe fixed together on the lid panel And
The urea water temperature management pipe is disposed near the bottom of the tank and the side surface of the measurement pipe, and a heat radiating plate is provided at the periphery of the portion of the urea water temperature management pipe located at the bottom of the tank body. The urea water tank according to claim 1, wherein the heat sink surrounds the suction port of the urea water supply pipe and the lower end of the measurement pipe.   5. The urea water tank according to claim 4, wherein the urea water supply pipe and the urea water temperature management pipe are joined so as to be capable of conducting heat in the tank body. A lid panel detachably attached to the upper surface of the tank body, and a pipe assembly member comprising urea water supply piping, urea water temperature management piping, various measurement piping and air vent piping fixed together on the lid panel With
The urea water temperature management pipe is disposed in the vicinity of the bottom of the tank and the side surface of the measurement pipe and is made of a thin plate around the portion of the urea water temperature management pipe located at the bottom of the tank body. A urea water tank piping unit characterized in that a box-shaped heat radiating portion is provided, and the suction port of the urea water supply piping and the lower end portion of the measuring piping are surrounded by the heat radiating portion.   The urea water tank piping unit according to claim 6, wherein the urea water supply pipe and the urea water temperature management pipe are joined to each other by a small thin plate so as to conduct heat in the tank body.   The urea water tank piping unit according to claim 6, wherein the heat dissipating part is composed of a top plate, a bottom plate, and two side plates formed in an L shape in a planar shape.   9. The urea water according to claim 8, wherein a hole through which each measurement pipe passes is formed in the upper surface plate, and a grommet formed so that the measurement pipe can be inserted and removed freely is fitted into the hole. Tank piping unit.

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