Patent Publication Number: US-2018045098-A1

Title: Heating structure, production method therefor, and pump module comprising same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is the national phase of International Application No. PCT/KR2016/001780, filed on 24 Feb. 2016, which is based upon and claims priority to Korean Patent Application No. 10-2015-0027573, filed on 26 Feb. 2015, the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a heating structure, a production method therefor, and a pump module including the same. 
     BACKGROUND 
     In general, an exhaust system for a diesel engine includes an exhaust gas post-processing unit, such as a selective catalyst reduction (SCR) unit, a diesel oxidation catalyst (DOC) unit, a catalyzed particulate filter (CPF), so as to reduce a nitrogen oxide (NOx) contained in exhaust gas. 
     Among them, an exhaust gas post-processing unit that applies SCR (hereinafter, referred to as an ‘SCR unit’) performs a function of injecting a reductant, such as an aqueous urea solution, into an inside of an exhaust pipe to reduce NOx in the exhaust gas into nitrogen and oxygen. 
     That is, in the SCR unit, when the reductant is injected into the inside of the exhaust pipe, the reductant can be changed to ammonia (NH 3 ) by heat of the exhaust gas, and NOx can be reduced into nitrogen gas (N 2 ) and water (H 2 O) as a catalyst reaction of NOx in the exhaust gas and ammonia using an SCR catalyst. 
     In this way, a system for supplying the aqueous urea solution to the SCR unit is required to inject the aqueous urea solution into the inside of the exhaust pipe using the SCR unit. 
     The system for supplying the aqueous urea solution basically includes a urea tank for storing the aqueous urea solution and a pump module that is disposed in the urea tank and supplies the aqueous urea solution to the SCR unit. 
     In the related art, as specific gravity of the aqueous urea solution increases in the winter season, freezing is sequentially performed from a lower portion of the urea tank, and as the volume of the aqueous urea solution expands due to freezing, great deformation may occur in an upper portion of the urea tank. 
     In addition, in the related art, a heating device and a pump are installed to be spaced by a predetermined distance apart from each other. Thus, it is not easy to melt the frozen aqueous urea solution that is present in the pump. 
     SUMMARY 
     Technical Problem 
     The present invention is directed to providing a heating structure for stably pumping a strongly alkaline aqueous urea solution using an injector and melting the frozen aqueous urea solution in the winter season, a production method therefor, and a pump module including the same. 
     Technical Solution 
     One aspect of the present invention provides a heating structure, which is for heating a pump installed in a tank so as to discharge a liquid stored in the tank to the outside of the tank, including: a flange installed on one surface of the interior of the tank; and a heating member coupled to one surface of the flange and provided on one side thereof with an accommodation groove in which at least a part of the pump is accommodated, wherein a first discharge tube of the pump having at least a part thereof accommodated in the accommodation groove extends toward the flange and is connected to a second discharge tube formed on the other surface of the flange outside the tank, and the heating member is formed to heat at least a part of the pump, at least a part of the first discharge tube, and at least a part of the second discharge tube. 
     The heating member may include: a body that extends in an inward direction of the tank; and a positive temperature coefficient (PTC) device coupled to an outside surface of the body, and the accommodation groove may be formed in an end that opens in the inward direction of the tank of the body. 
     The heating structure may further include a cover coupled to the body so as to cover and seal the PTC device. 
     A protrusion may be formed on one side of the PTC device and may protrude toward the flange, and a plug connected to the PTC device may be formed on an end of the protrusion, and a first groove may be recessed in the one surface of the flange so that the protrusion is inserted into the first groove, and a socket corresponding to the plug may be formed in a center of the first groove. 
     The heating structure may further include a first sealing member formed on an outer circumferential surface of the protrusion. 
     The heating structure may further include: a mounting groove formed in one side surface of the body so that the PTC device is inserted into the body through the mounting groove; and a wall portion formed at a circumference of the mounting groove, wherein the cover may be coupled to the wall portion to cover and seal the PTC device and to fix the PTC device to the body. 
     The heating structure may further include a gasket disposed between the wall portion and the cover and sealing a space between the wall portion and the cover. 
     The heating structure may further include a power cutoff unit that cuts off power supplied to the PTC device when the power cutoff unit is electrically connected to the PTC device and the PTC device is at a Curie temperature or higher. 
     The heating structure may further include a temperature sensor that is installed on one surface of the flange and detects a temperature of the liquid. 
     A second groove may be formed in one surface of the flange to accommodate at least a part of the first discharge tube, and one end of the body capable of heating at least a part of the first discharge tube may be accommodated in the second groove together with at least a part of the first discharge tube. 
     One end of the body may be formed to heat a part of the second discharge tube. 
     A connection tube may be formed in the second groove of the flange, may protrude from an interior of the second groove of the flange, may extend toward the heating member and may connect the first discharge tube to the second discharge tube. 
     The heating structure may further include a linear discharge tube coupled to the first discharge tube, wherein the discharge tube may be disposed in the connection tube while being coupled to the first discharge tube. 
     The heating structure may further include a second sealing member formed at an outer circumferential surface of the discharge tube so as to seal a space between the discharge tube and the connection tube. 
     The tank may be a storage tank for storing an aqueous urea solution. 
     Another aspect of the present invention provides a pump module including: a pump installed in a storage tank so as to discharge a liquid stored in the storage tank to an outside of the storage tank; the above-described heating structure disposed to surround an outside surface of the pump; a coupling member coupled to an outside of the pump so as to couple the heating structure to the flange; and a filter coupled to the flange to surround the pump, the coupling member and the heating structure and filtering the liquid supplied to the pump. 
     Still another aspect of the present invention provides a production method for a heating structure, including: providing a body having a mounting groove formed in one side surface thereof and a wall portion provided at a circumference of the mounting groove; inserting a positive temperature coefficient (PTC) device into the mounting groove; installing a gasket at the wall portion and coupling a cover to the wall portion; and injection molding a surface of the body to which the cover is coupled, to form a housing. 
     Advantageous Effects 
     In a heating structure according to an embodiment of the present invention and a production method therefor, a frozen aqueous urea solution can be melted using a positive temperature coefficient (PTC) device capable of heating the aqueous urea solution, and damage caused by electrical overload can be prevented. 
     In a pump module according to an embodiment of the present invention, a strongly alkaline aqueous urea solution can be stably pumped using an injector. 
     In a heating structure according to an embodiment of the present invention and a pump module including the same, a flange mounted on a lower portion of a tank is provided so that installation of the heating structure in the pump module is simple. 
     In a heating structure according to an embodiment of the present invention, a body is formed to heat a part of a first discharge tube and a part of a second discharge tube so that the frozen aqueous urea solution that is present in the discharge tube of the pump module can be efficiently melted. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view showing a state in which a pump module having a heating structure mounted thereon according to an embodiment of the present invention is installed in a tank. 
         FIG. 2  is a perspective view of the pump module having the heating structure mounted thereon according to an embodiment of the present invention. 
         FIG. 3  is a cross-sectional view taken along a line A-A of  FIG. 2 , wherein arrows represent a flow of a liquid. 
         FIG. 4  is an exploded perspective view of the heating structure according to an embodiment of the present invention. 
         FIG. 5  is a cross-sectional view of a flange of the heating structure according to an embodiment of the present invention, wherein arrows represent the flow of the liquid. 
         FIG. 6  is a perspective view of a heating member of the heating structure according to an embodiment of the present invention. 
         FIG. 7  is a bottom perspective view of the heating member of the heating structure according to an embodiment of the present invention. 
         FIG. 8  is a perspective view of a positive temperature coefficient (PTC) device coupled to a body of the heating structure according to an embodiment of the present invention. 
         FIG. 9  is a perspective view of a pump installed at the heating member of the heating structure according to an embodiment of the present invention. 
         FIG. 10  is a perspective view of the heating member of the heating structure according to an embodiment of the present invention installed at the flange. 
         FIG. 11  is a flowchart illustrating a production method for the heating structure, according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the attached drawings in order to enable those of ordinary skill in the art to easily embody and practice the invention. The present invention can be implemented in several different forms and is not limited to the exemplary embodiments disclosed below. In order to clearly describe the present invention, portions irrelevant to the description are omitted in the drawings, and like reference numerals throughout the specification denote like elements. 
     In the present specification, it is to be understood that the terms such as “including” or “having,” etc., are intended to indicate the existence of the features, numbers, steps, actions, components, parts, or combinations thereof disclosed in the specification, and are not intended to preclude the possibility that one or more other features, numbers, steps, actions, components, parts, or combinations thereof may exist or may be added. It will be understood that, when a portion such as a layer, a film, a region or a plate is referred to as being “on” another portion, the portion can be “directly on” another portion or on intervening portions. In contrast, when a portion such as a layer, a film, a region or a plate is referred to as being “under” another portion, the portion can be “directly under” another portion or under intervening portions. 
     Hereinafter, a heating structure according to an embodiment of the present invention and a pump module including the same will be described in more detail with reference to the drawings. 
       FIG. 1  is a perspective view showing a state in which a pump module having a heating structure mounted thereon according to an embodiment of the present invention is installed in a tank.  FIG. 2  is a perspective view of the pump module having the heating structure mounted thereon according to an embodiment of the present invention.  FIG. 3  is a cross-sectional view taken along a line A-A of  FIG. 2 , wherein arrows represent a flow of a liquid. 
     Referring to  FIGS. 1 through 3 , a pump module  3  having a heating structure  1  mounted thereon according to an embodiment of the present invention may include a pump  9 , the heating structure  1 , a coupling member  13 , and a filter  15 . 
     In this case, the pump module  3  may be installed in a tank  7  in which a liquid is stored, and may pump the liquid using an injector (not shown) installed outside the tank stably. 
     In addition, the pump module  3  may perform a function of adjusting the temperature and level of the liquid stored in the tank  7  and filtering the liquid stored in the tank  7  and may melt the frozen liquid using the heating structure  1  installed therein. This enables the frozen liquid to be firstly melted before the pump  9  operates, so that the pump can operate smoothly. 
     Referring to  FIGS. 1 through 3 , in an embodiment of the present invention, the liquid stored in the storage tank  7  may be an aqueous urea solution  5  used as a reductant. In this case, the aqueous urea solution  5  is colorless, odorless, nonpoisonous, unburnable, and strongly alkaline (PH 10 or higher) and is mixed in water at the ratio of 32.5%. 
     A freezing point of the aqueous urea solution  5  that is strongly alkaline is −11.5° C., and a volume of the aqueous urea solution  5  at the freezing point expands by  11 %. Thus, when the aqueous urea solution  5  stored in the pump module is frozen, the volume of the aqueous urea solution expands, which may cause damage of the pump module  3 . 
     Thus, the pump module  3  may be installed in the tank  7  in which the aqueous urea solution is stored, and may pump the strongly alkaline aqueous urea solution using the injector (not shown) installed outside the tank stably. 
     Referring to  FIG. 3 , in an embodiment of the present invention, the pump  9  is installed in the tank  7  and pumps the aqueous urea solution  5  stored in the tank  7  to the outside of the tank. 
     Meanwhile, a suction tube  12  and a first discharge tube  11  of the pump  9  may be formed on a lower side surface of the pump while being adjacent to each other. Thus, the aqueous urea solution  5  is sucked into the pump via the suction tube  12  formed on the lower side surface of the pump and is discharged to the outside of the pump via the first discharge tube  11 . 
     The suction tube  12  and the first discharge tube  11  of the pump  9  are installed adjacent to each other so that the aqueous urea solution  5  suctioned via the suction tube  12  does not pass through a motor (not shown) disposed in the pump but is directly discharged via the first discharge tube  11  and thus the motor can be protected. 
     Meanwhile, the heating structure  1  according to an embodiment of the present invention is disposed to surround an outside surface of the pump  9 . In this case, the heating structure  1  may transfer heat to the pump  9  and may melt the frozen aqueous urea solution  5 . 
     Referring to  FIG. 3 , in an embodiment of the present invention, the coupling member  13  is provided to couple the heating structure  1  to the pump  9 . 
     In this case, the coupling member  13  may be coupled to the outside of the pump  9  to couple the heating structure  1  to a flange  50  so that the heating structure  1  can be fixed to the interior of the tank  7 . 
     Meanwhile, referring to  FIGS. 1 through 3 , the filter  15  may be disposed to surround the pump  9 , the coupling member  13 , and the heating structure  1 . In this case, the filter  15  may be coupled to the flange  50 , and a plurality of filter media  17  may be disposed on an outside surface of the filter. 
     In this case, the filter  15  filters the aqueous urea solution  5  stored in the tank  7  using the filter media  17  and supplies the filtered aqueous urea solution  5  to the pump  9 , as illustrated in  FIG. 3 . 
       FIG. 4  is an exploded perspective view of a heating structure according to an embodiment of the present invention. 
     Referring to  FIG. 4 , the heating structure  1  according to an embodiment of the present invention may include a heating member  30  and the flange  50  having the heating member installed therein. In this case, the heating structure  1  including the heating member  30  may transfer heat to the pump  9  to melt the frozen aqueous urea solution  5 . 
       FIG. 5  is a cross-sectional view of a flange of the heating structure according to an embodiment of the present invention, wherein arrows represent the flow of the liquid.  FIG. 6  is a perspective view of a heating member of the heating structure according to an embodiment of the present invention.  FIG. 7  is a bottom perspective view of the heating member of the heating structure according to an embodiment of the present invention.  FIG. 8  is a perspective view of a positive temperature coefficient (PTC) device coupled to a body of the heating structure according to an embodiment of the present invention. 
     Referring to  FIGS. 5 through 8 , in an embodiment of the present invention, the heating member  30  may include a housing  31 , a body  32 , and a PTC device  41 . 
     The heating structure  1  according to an embodiment of the present invention may transfer heat to the PTC device  41 , at least a part of the pump  9 , and at least a part of the first discharge tube  11  and the second discharge tube  57  so as to melt the frozen aqueous urea solution  5 . 
     In addition, when electrical overload is applied to the PTC device  41  due to characteristics of the PTC device  41 , power is cut off so that damage caused by electrical overload can be prevented. 
     Meanwhile, referring to  FIGS. 1 and 3 , the body  32  may extend in an inward direction of the tank  7 , and for example, the body may extend in a vertical direction of the tank, as illustrated in  FIG. 3 . 
     In an embodiment of the present invention, referring to  FIG. 3 , the body  32  that transfers heat may be installed in the housing  31 . The housing  31  may be a resin injection-molded product manufactured by injection molding the body  32  using a resin. Thus, the shape of the body  32  and the shape of the housing  31  may be the same. 
     In addition, referring to  FIGS. 3 through 5 , an accommodation groove  33  may be formed in one end of the body  32  that opens in the inward direction of the tank  7 , for example, in one end of the body  32  that opens in an upward direction of the tank, as illustrated in  FIG. 3 . 
     In this case, the pump  9  may be vertically inserted into the accommodation groove  33  formed in the body  32 . In addition, a plurality of first inlets  34  may be formed on a lower side surface of the body  32 , as illustrated in  FIG. 7 , and the plurality of first inlets may be connected to the suction tube  12  of the pump  9 . 
     In this case, the aqueous urea solution  5  may pass through the first inlets  34  of the body  32  and may be introduced into the inside of the pump via the suction tube  12  of the pump  9 . 
     Referring to  FIG. 6 , the body  32  may be formed of aluminum and may have a cylindrical shape with circular cross-sections. However, the body  32  may have one side surface with a plate shape so that the PTC device  41  can be coupled to the outside surface of the body  32 . 
     In addition, the body  32  includes the pump  9  disposed therein and thus surrounds the pump so that heat generated in the body can be directly transferred to the pump. 
     In this case, the PTC device  41  may have a plate shape with rectangular cross-sections, as illustrated in  FIG. 8 , and may generate heat by supplied electrical energy due to characteristics of the PTC device. 
     Meanwhile, referring to  FIG. 8 , in an embodiment of the present invention, a mounting groove  35  may be formed in one side surface of the body  32  so that the PTC device  41  can be inserted into the body  32  through the mounting groove  35 . In addition, a wall portion  37  may protrude from a circumference of the mounting groove  35 . 
     In an embodiment of the present invention, the PTC device  41  may be coupled to the body  32  through a cover  43 . In this case, the cover  43  may cover and seal the PTC device  41  and simultaneously may enable the PTC device to be coupled to the body  32 . 
     Referring to  FIG. 8 , the cover  43  may have rectangular cross-sections but may have any shape in which the cover  43  covers and seals the PTC device  41 . 
     In addition, the cover  43  may include a screw hole  43   a  formed in a corner of the cover so that the PTC device  41  can be coupled to the body  32  using a bolt  44  through the screw hole  43   a.    
     Meanwhile, referring to  FIG. 8 , in an embodiment of the present invention, the cover  43  may be coupled to the wall portion  37  that protrudes from the circumference of the mounting groove  35 . The cover  43  may be coupled to the wall portion  37  to cover and seal the PTC device  41 . Thus, the PTC device can be fixed to the body  32 . 
     In this case, a gasket  39  may be installed between the wall portion  37  and the cover  43  to seal a space between the wall portion and the cover. The gasket  39  may enable the aqueous urea solution  5  not to be permeated into the PTC device  41 . 
     Meanwhile, the heating structure  1  according to an embodiment of the present invention may include a power cutoff unit (not shown). 
     The power cutoff unit may be a power sensor, and the power sensor may be electrically connected to the PTC device  41  so that, when the PTC device is at a Curie temperature or higher, the power sensor may cutoff power supplied to the PTC device. In this case, the Curie temperature is a temperature at which a material loses magnetism. 
     Referring to  FIG. 8 , a plug  47  may be formed on a lower end of the PTC device  41  to supply electrical energy to the PTC device. The plug  47  is electrically connected to the PTC device  41 . 
     Referring to  FIGS. 6 through 8 , a protrusion  45  may be formed on one side of the PTC device  41  and may protrude toward the flange  50 . 
     An insertion hole  45 a may be formed in one end of the protrusion  45 , i.e., in a lower surface of the protrusion, as illustrated in  FIG. 7 , so that the plug  47  can be inserted into and pass through the insertion hole  45 a. In this case, the plug  47  may be inserted into the insertion hole  45 a and may be exposed to the outside of the protrusion. 
       FIG. 9  is a perspective view of a pump installed at the heating member of the heating structure according to an embodiment of the present invention.  FIG. 10  is a perspective view of the heating member of the heating structure according to an embodiment of the present invention installed at the flange. 
     Referring to  FIG. 10 , a first groove  51  may be recessed in one surface of the flange  50  so that the protrusion  45  can be inserted into the one surface of the flange  50  through the first groove  51 . In addition, a socket  55  to be coupled to the plug  47  may be formed in the center of the first groove  51 . 
     Referring to  FIGS. 9 and 10 , the protrusion  45  and the first groove  51  may have corresponding shapes. For example, the protrusion  45  and the insertion hole  45 a may have circular cross-sections, as illustrated in  FIG. 10 . 
     In addition, a radius of an outer circumferential surface of the protrusion  45  and a radius of the first groove  51  may be formed in such a way that, when the protrusion is inserted into the first groove, the plug  47  and the socket  55  can be sealed at the radius of the outer circumferential surface of the protrusion  45  and the radius of the first groove  51 . That is, the radius of the outer circumferential surface of the protrusion  45  may be smaller than the radius of the first groove  51 . 
     In addition, a first sealing member  49  may be formed on the outer circumferential surface of the protrusion  45  so as to seal the first groove and the protrusion when the protrusion is inserted into the first groove  51 . 
     Meanwhile, referring to  FIGS. 2 through 4 , the flange  50  may be installed on one surface of the interior of the tank  7 , i.e., on the lower side surface of the tank, as illustrated in  FIG. 2 , to block a hole (not shown) formed in a lower portion of the tank. That is, the flange  50  may be mounted on the lower portion of the tank  7  so that installation of the flange  50  is simple. 
     In this case, referring to  FIG. 3 , the pump  9 , the heating member  30 , the filter  15 , and the coupling member  13  may be installed on an upper portion of the flange  50  and may be fixed to the interior of the tank  7 . In addition, a lower portion of the flange  50  may be exposed to the outside of the tank  7  so that the aqueous urea solution  5  can be discharged to the outside of the tank. 
     Referring to  FIGS. 3 and 4 , the flange  50  may have a cross section in a shape of a circular plate and may protrude in a downward direction of the circular plate. Embodiments of the present invention are not limited thereto. 
     Referring to  FIG. 4 , the first groove  51  and a second groove  53  may be formed in a top surface of the flange  50 , and a connection tube  59  may be provided in the second groove. In addition, a second discharge tube  57  connected to the connection tube  59  may be provided on a lower side of the flange  50 . 
     Referring to  FIG. 4 , in an embodiment of the present invention, the second groove  53  of the flange  50  may be formed in one surface of the flange, for example, in the top surface of the flange. 
     Referring to  FIGS. 4 and 5 , at least a part of the first discharge tube  11  formed on the lower side surface of the pump  9  may be accommodated in the second groove  53 . 
     Meanwhile, referring to  FIGS. 4 and 5 , one end of the body  32 , for example, a lower end of the body  32  may be accommodated in the second groove  53  together with at least a part of the first discharge tube  11 . 
     In this case, the body  32  may protrude in such a way that a part of the lower end of the body  32  can be inserted into the second groove  53 . In addition, at least a part of the first discharge tube  11  may be heated by the protruding body  32 . 
     Referring to  FIG. 3 , the second discharge tube  57  is a passage through which the aqueous urea solution  5  is discharged to the outside of the flange  50 . Meanwhile, one end of the body  32  may be formed to heat a part of the second discharge tube  57 . 
     That is, the lower end of the protruding body  32  may extend in a horizontal direction to heat a part of the second discharge tube  57 . 
     In this case, the lower end of the protruding body  32  may be formed to correspond to the shape of the second discharge tube so as to heat a part of the second discharge tube  57 . As illustrated in  FIG. 4 , the shape of the second discharge tube  57  may be a circular tube shape, and in this case, the lower end of the body having a semicircular shape may be formed to surround a part of an upper side of the second discharge tube  57 . 
     Referring to  FIGS. 4 and 5 , in an embodiment of the present invention, the second discharge tube  57  may be formed on the other side of the flange  50 , for example, on the lower side of the flange, as illustrated in  FIG. 4 . 
     In this case, a second inlet  57   a  of the second discharge tube  57  may be connected to the connection tube  59 , and a discharge port  57   b  of the second discharge tube  57  may extend in the horizontal direction, may pass through side surfaces of the flange  50  and may be exposed to the outside of the flange  50 , as illustrated in  FIG. 4 . 
     Meanwhile, in an embodiment of the present invention, the flange  50  may include the connection tube  59  that is formed in the inside of the second groove  53  and connects the first discharge tube  11  to the second discharge tube  57 , as illustrated in  FIGS. 4 and 5 . 
     In this case, the connection tube  59  may protrude from the inside of the second groove  53  toward the heating member  30 . 
     Meanwhile, referring to  FIGS. 5 and 10 , a discharge tube  61  may be vertically installed in the connection tube  59 . In this case, the discharge tube  61  may have a linear shape and may be coupled to the first discharge tube  11  of the pump  9 . 
     In this case, a second sealing member  65  may be formed on an outer circumferential surface of the discharge tube  61  so as to seal a space between the discharge tube  61  and the connection tube  59 . 
     Meanwhile, as illustrated in  FIG. 5 , a pressure sensor  63  may be mounted on the second inlet  57   a  of the second discharge tube  57 . The pressure sensor  63  compares a current actual measurement pressure with a target pressure to feedback control the pressure of the aqueous urea solution  5  in real time. 
     In an embodiment of the present invention, the first discharge tube  11 , the second discharge tube  57 , the connection tube  59 , and the discharge tube  61  may have a tubular shape with circular cross-sections so that the aqueous urea solution  5  can flow therethrough. However, embodiments of the present invention are not limited thereto. 
     Meanwhile, the heating structure  1  according to an embodiment of the present invention may include a temperature sensor (not shown) that is installed on one surface of the flange  50  and detects the temperature of the aqueous urea solution  5  that is a liquid. 
     In this case, in an embodiment of the present invention, the temperature sensor may detect the temperature of the aqueous urea solution  5  inside the tank  7  to control an operation of the heating structure  1  and to maintain a constant temperature of the aqueous urea solution around the pump  9 . 
     In an embodiment of the present invention, the first sealing member  49  and the second sealing member  65  may seal the first groove  51  and the protrusion and the space between the discharge tube  61  and the connection tube  59 , respectively, so that the aqueous urea solution  5  does not permeate into the heating structure  1  and the pump module  3  including the same. 
     In this case, the first sealing member  49  and the second sealing member  65  may be compressed at a set compression ratio, may have set thicknesses, and may be manufactured in the form of an O-ring formed of fluorine silicon, for example. 
       FIG. 11  is a flowchart illustrating a production method for the heating structure, according to an embodiment of the present invention. 
     Referring to  FIG. 11 , the production method for the heating structure may include providing a body having a mounting groove formed in one side surface thereof and a wall portion provided at a circumference of the mounting groove (S 10 ), inserting a PTC device into the mounting groove (S 20 ), installing a gasket at the wall portion and coupling a cover to the wall portion (S 30 ), and injection molding the surface of the body to which the cover is coupled, to form a housing (S 40 ). 
     Thus, the PTC device  41  in a sealed state may be installed at the body  32 . Also, the surface of the body  32  having the PTC device  41  installed therein may be injection-molded to form the housing  31 . 
     Meanwhile, in providing of the body having the mounting groove formed in one side surface thereof and the wall portion provided at the circumference of the mounting groove (S 10 ), the mounting groove  35  may be formed in one side surface of the body  32 , and the wall portion  37  protrudes from the circumference of the mounting groove. 
     In addition, in inserting of the PTC device into the mounting groove (S 20 ), the PTC device  41  is inserted into and is installed in the mounting groove  35 . In this case, the area of the mounting groove  35  may be greater than or the same as the area of the PTC device  41 . 
     Meanwhile, in installing of the gasket at the wall portion and coupling the cover to the wall portion (S 30 ), the gasket  39  is installed at or applied to the protruding wall portion  37 , and the cover  43  is coupled to the wall portion having the gasket installed therein, to seal the PTC device  41 . 
     In addition, in injection molding of the surface of the body to which the cover is coupled, to form the housing (S 40 ), the PTC device  41  is installed to inject a molding material into the body  32  to which the cover  43  is coupled, and to manufacture the housing  31 . 
     In this case, the housing  31  may have the same shape as that of the body  32 . However, embodiments of the present invention are not limited thereto. 
     Meanwhile, the heating member  30  may include the housing  31 , the body  32 , and the PTC device  41 . 
     In a heating structure according to an embodiment of the present invention and a production method therefor, a PTC device capable of heating an aqueous urea solution that is easily frozen in the winter season is provided so that the frozen aqueous urea solution can be melted. 
     In a pump module according to an embodiment of the present invention, a strongly alkaline aqueous urea solution can be stably pumped using an injector. 
     In a heating structure according to an embodiment of the present invention and a pump module including the same, a flange mounted on a lower portion of a tank is provided so that installation of the heating structure in the pump module is simple. 
     In a heating structure according to an embodiment of the present invention, a body is formed to heat a part of a first discharge tube and a part of a second discharge tube so that the frozen aqueous urea solution that is present in the discharge tube to be discharged to the outside of the pump module can be efficiently melted. 
     While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. 
     INDUSTRIAL APPLICABILITY 
     In a heating structure according to an embodiment of the present invention and a production method therefor, a PTC device capable of heating an aqueous urea solution is provided so that the frozen aqueous urea solution can be melted and damage caused by electrical overload can be prevented. 
     In a pump module according to an embodiment of the present invention, a strongly alkaline aqueous urea solution can be stably pumped using an injector. 
     In a heating structure according to an embodiment of the present invention and a pump module including the same, a flange mounted on a lower portion of a tank is provided so that installation of the heating structure in the pump module is simple. 
     In a heating structure according to an embodiment of the present invention, a body is formed to heat a part of a first discharge tube and a part of a second discharge tube so that the frozen aqueous urea solution that is present in the discharge tube can be efficiently melted.