Abstract:
A manufacturing method and structure of a heat exchanger for a bathing shower involves two plates welded together to form a passage for cold water. Hot water from the shower drips onto the upper plate and transfer heat to cold water flowing through the passage between the plates. The upper plate may be spot welded to the lower plate at bottoms of frustoconical indentations in the lower plate, the plates may sandwich an adiabatic layer, and/or the passage between the plates may be formed by pipes situated between the plates.

Description:
FIELD OF THE PRESENT INVENTION 
       [0001]    The present invention relates to an energy saving heat exchanger for a bathing shower, the heat exchanger having a simple structure that significantly decreases manufacturing time and costs and provides enhanced energy saving efficiency so as to make the heat exchanger more affordable and attractive to consumers. Thus, the invention not only provides increased popularity but also offers environmental protection due to increased energy saving and reduced carbon emissions. 
       BACKGROUND OF THE INVENTION 
       [0002]    For the purpose of reducing their carbon footprint, many heat exchangers for bathing showers used in households have been introduced in the market. The design concept is that incoming cold tap water running through the heat exchanger is heated up by hot waste water from the shower, which serves as a thermal source, so that the temperature of the tap water output from the heat exchanger becomes warmer than that of the incoming tap water, the output being directed into an inlet pipe for the water heater of the bathing shower. As a result, the temperature of the inlet water for the water heater of the bathing shower is increased to save energy required for heating the water. However, due to the complicated structural design of these currently marketed heat exchangers, the manufacturing process and related machinery are relatively complex, so that not only are the selling price and manufacturing cost kept at a high level without possibility of lowering, but marketing promotion and popularity are retarded, discouraging purchasing and use by consumers and thereby limiting benefits to the environment. Therefore, simplification of the structural design and reduction in manufacturing costs of heat exchangers for bathing showers has become a critical need. 
       SUMMARY OF THE INVENTION 
       [0003]    The primary object of the present invention is to provide a manufacturing method and structure of a heat exchanger for a bathing shower that is relatively simple to not only substantially decrease overall manufacturing costs, resulting in reduced selling price and increased affordability for consumers, but also in enhanced overall energy saving effect and prolonged service life span to encourage purchasing by consumers. Thus, the present invention not only facilitates promotion and increases popularity of bathing shower heat exchangers, but also achieves environmental protection by energy saving and reduced carbon footprint. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]      FIG. 1  is a flow chart showing a manufacturing process for the first embodiment of the present invention. 
           [0005]      FIG. 2  is a perspective view showing an upper metal plate and a lower metal plate for the first embodiment of the present invention. 
           [0006]      FIG. 3  is a perspective view showing the upper metal plate for the first embodiment of the present invention. 
           [0007]      FIG. 4  is a perspective view showing the lower metal plate for the first embodiment of the present invention. 
           [0008]      FIG. 5  is a first operational view showing spot welding of an upper metal plate and a lower metal plate for the first embodiment of the present invention. 
           [0009]      FIG. 6  is a second operational view showing spot welding of an upper metal plate and a lower metal plate for the first embodiment of the present invention. 
           [0010]      FIG. 7  is a perspective view showing an intermediate product of the manufacturing process for the first embodiment of the present invention. 
           [0011]      FIG. 8  is a sectional view taken along line  8 - 8  as indicated in  FIG. 7 . 
           [0012]      FIG. 9  is a cross sectional view showing application of a further processing step to the intermediate product of  FIG. 7  and  FIG. 8  in order to obtain a heat exchanger for a bathing shower according to the first embodiment of the present invention. 
           [0013]      FIG. 10  is a perspective view showing a heat exchanger for a bathing shower made by a modified manufacturing process for the first embodiment of the present invention. 
           [0014]      FIG. 11  is a sectional view taken along line  11 - 11  as indicated in  FIG. 10 . 
           [0015]      FIG. 12  is a sectional view taken along line  12 - 12  as indicated in  FIG. 10 . 
           [0016]      FIG. 13  is a perspective view showing an installation of a heat exchanger for a bathing shower made by the manufacturing process for the first embodiment of the present invention. 
           [0017]      FIG. 14  is a cross sectional view showing an installation of a heat exchanger for a bathing shower made by the manufacturing process for the first embodiment of the present invention. 
           [0018]      FIG. 15  is a sectional view taken along line  15 - 15  as indicated in  FIG. 14 . 
           [0019]      FIG. 16  is a perspective exploded view showing a heat exchanger for a bathing shower according to a second embodiment of the present invention. 
           [0020]      FIG. 17  is a perspective schematic view showing an installation of a heat exchanger for a bathing shower according to the second embodiment of the present invention. 
           [0021]      FIG. 18  is a sectional view taken along line  18 - 18  as indicated in  FIG. 17 . 
           [0022]      FIG. 19  is a sectional view taken along line  19 - 19  as indicated in  FIG. 17 . 
           [0023]      FIG. 20  is a perspective exploded view showing a heat exchanger for a bathing shower according to a third embodiment of the present invention. 
           [0024]      FIG. 21  is a perspective assembled view showing a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0025]      FIG. 22  is a sectional view taken along line  22 - 22  as indicated in  FIG. 21 . 
           [0026]      FIG. 23  is a perspective view showing a metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0027]      FIG. 24  is a top view showing a metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0028]      FIG. 25  is a cross sectional view showing a metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0029]      FIG. 26  is a first top view showing a modified metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0030]      FIG. 27  is a second top view showing another modified metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
           [0031]      FIG. 28  is a third top view showing the other modified metal tubular array of a heat exchanger for a bathing shower according to the third embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0032]      FIG. 1  and  FIG. 2  to  FIG. 9  show processing steps of a manufacturing method for embodiments of a “heat exchanger for bathing shower”, as follows: 
         [0033]    a. taking non-magnetic corrosion-resistant metal as a material, making an upper metal plate  10  and a lower metal plate  20  of same area by a stamp-shaping process (as shown in  FIG. 2 ); 
         [0034]    b. stamping a plurality of frustoconical indentations  13  in parallel, evenly-shaped rows, the indentations extending from a top surface  11  towards a bottom surface  12  of the upper metal plate  10  (as shown in  FIG. 3 ), and stamping a water intake  21  and a water outtake  22  in the lower metal plate  20  (as shown in  FIG. 4 ); 
         [0035]    c. after stacking the bottom surface  12  of the upper metal plate  10  on the lower metal plate  20  in a flush manner, placing the upper and lower metal plates  10  and  20  on a spot welder S for spot welding (as shown in  FIG. 5 ) so that each indentation bottom  14  of every frustoconical indentation  13  in a row is fusion welded in a predetermined order with corresponding spots on the lower metal plate  20  (as shown in  FIG. 8 ) while a cathode roller R of the spot welder S bends the integral entity of the welded upper metal plate  10  and lower metal plate  20  into a camber plate (as shown in  FIG. 6 ); 
         [0036]    d. sealing all peripherals around the integral entity formed by the welded upper metal plate  10  and lower metal plate  20  (as shown in  FIG. 7 ); and 
         [0037]    e. respectively welding a pipe fitting J to each water intake  21  and water outtake  22  individually on the lower metal plate  20  for finishing the manufacturing process (as shown in  FIG. 9 ). 
         [0038]    As shown in  FIG. 8  and  FIG. 9 , the structure of a “heat exchanger for bathing shower” in the present invention manufactured by the process described above includes an upper metal plate  10  and a lower metal plate  20 , wherein: 
         [0039]    The upper metal plate  10 , which is a rectangular cambered plate made of non-magnetic corrosion-resistant metal by a stamp-shaping process, has a plurality of frustoconical indentations  13  arranged in parallel evenly spaced rows stamped into top surface  11  and extending towards bottom surface  12  such that the diameter of each indentation bottom  14  is smaller than that of the opening of the respective frustoconical indentation  13  (as shown in  FIG. 8  and related enlarged view); and 
         [0040]    The lower metal plate  20 , which is a rectangular cambered plate made of non-magnetic corrosion-resistant metal by a stamp-shaping process with a same area as the upper metal plate  10  for being stacked beneath bottom surface  12  of the upper metal plate  10  by spot welding, has a water intake  21  and a water outtake  22  stamped therein such that a pipe fitting J may be respectively welded to each water intake  21  and water outtake  22  individually (as shown in  FIG. 9 ) with the result that each indentation bottom  14  of every frustoconical indentation  13  in each row is fusion welded with corresponding spots on the lower metal plate  20 , and all peripherals around the upper metal plate  10  and lower metal plate  20  are sealed by welding into an integral entity (as shown in  FIG. 7 ) so that the interior space enclosed by the upper metal plate  10  and lower metal plate  20 , other than that occupied by the plurality of frustoconical indentations  13 , creates a hollow space  15  for water circulation (as shown in  FIG. 9  and related enlarged view). 
         [0041]    As shown in  FIG. 1 ,  FIG. 10  and  FIG. 12 , the process step d can further include an additional step d′, in which two interlaced comb-like parallel groove sets  16  are created on the top surface  11  of the upper metal plate  10  such that every adjacent prong in each of the groove sets  16  is separated by an even number, such as four, of rows of frustoconical indentations  13  (as shown in  FIGS. 10 and 12 ). As a result, all prong grooves in each of the groove sets  16  is interlaced in facing manner to enhance the directional uniformity of water circulation in the hollow space  15  surrounding the frustoconical indentations  13 , thereby promoting the efficiency of the heat exchange. 
         [0042]      FIG. 13  through  FIG. 15  illustrate installation and operation of a heat exchanger for a bathing shower of the present invention. For installation, the heat exchanger is situated in a tiered basin  2  of the floor of bathroom  1 . Then, a tap water pipe P is connected to the pipe fitting J of the water intake  21  in the lower metal plate  20 . Third, an inlet pipe  101  of a water heater  100  is connected to the pipe fitting J of the water outtake  22  in the lower metal plate  20 . Finally, a treading plate  3  with plural bores h is positioned over the top opening of the tiered basin  2  to cover the tiered basis  2  and finish the installation (as shown in  FIG. 13  and  FIG. 14 ). For shower operation, hot shower water W, which comes from the water heater  100  via outlet pipe  102  and exits a shower sprayer  103 , is used for showering on the user&#39;s body. The hot shower water W then drips to the top surface  11  of the upper metal plate  10  via plural bores h in the treading plate  3  on the floor of bathroom  1 . Third, cold tap water W 1 , which comes from the tap water pipe P via the pipe fitting J of the water intake  21  on the lower metal plate  20  and flows into the hollow space  15  enclosed by the bottom surface  12  of the upper metal plate  10  and the lower metal plate  20 , will perform heat exchange by absorbing thermal energy of the hot shower water W that has already dripped to the top surface  11  of the upper metal plate  10 . Fourth, the cold tap water W 1  will become warm water W 2  after the heat exchange. Fifth, the warm heat-exchanged water W 2  will flow into the inlet pipe  101  of the water heater  100  via the pipe fitting J of the water outtake  22  on the lower metal plate  20  to save heating energy consumption of the water heater  100  (as shown in  FIG. 13  and  FIG. 14 ); and finally, the waste hot shower water W, which has been heat exchanged, will be discharged via a drain  4  at the bottom of the tiered basin  2  (as shown in  FIG. 14  and  FIG. 15 ). 
         [0043]    It will be understood by those skilled in the art from the foregoing disclosure of the manufacturing process for the present invention that stainless steel plate #SUS303 or #SUS304 can be selected as a material of both the upper metal plate  10  and lower metal plate  20  for further stamping and spot welding into an integral entity using existing metalworking processes and machinery or equipment so that the selling price and manufacturing cost can be lowered to increase affordability, facilitate marketing promotion, and enhance popularity with consumers. Therefore, the invention will have a significant effect in advocating energy saving for a water heater  100  by recycling the hot shower water W. Moreover, the use of frustoconical indentations  13  to temporarily hold hot shower water W in the upper metal plate  10  will increase heat exchanging time with the cold tap water W 1  to increase heat exchanging efficiency and promote the energy saving effect of the water heater  100 . 
         [0044]      FIGS. 16 through 19  show a heat exchanger for a bathing shower according to a second embodiment of the present invention. The heat exchanger for a bathing shower in this embodiment includes an upper metal plate  30 , a lower metal plate  20 , a sandwiched adiabatic layer  50 , a deck  40 , a right flank  60  and a left flank  70 , wherein: 
         [0045]    The upper metal plate  30 , which is a rectangular cambered plate with a pair of longitudinal tucked edges  36  made of non-magnetic corrosion-resistant metal by a stamp-shaping process, has plural frustoconical indentations  33  arranged in evenly spaced parallel rows stamped into top surface  31  and towards bottom surface  32  such that the diameter of each indentation bottom  34  is smaller than that for the opening of the frustoconical indentation  33 ; 
         [0046]    The lower metal plate  20 , which is a rectangular cambered plate made of non-magnetic corrosion-resistant metal by a stamp-shaping process with an area smaller than that of the upper metal plate  30 , is stacked beneath bottom surface  32  of the upper metal plate  30  and adhered by spot welding. The lower metal plate  20  has a water intake  21  and a water outtake  22  stamped therein such that an inlet duct  23  is welded to the water intake  21  and an outlet duct  24  is welded to the water outtake  22  respectively (as shown in  FIG. 16 ); Thereby, each indentation bottom  34  of every frustoconical indentation  33  in each row is fusion welded with a corresponding spot on the lower metal plate  20 , and all peripherals around the upper metal plate  30  and lower metal plate  20  are sealed by welding into an integral entity (as shown in  FIG. 18 ) so that the entire interior space between the upper metal plate  30  and lower metal plate  20 , other than the space occupied by frustoconical indentations  33 , forms a hollow space  35  for water circulation (as shown in  FIG. 18 ,  FIG. 19  and related enlarged view); 
         [0047]    The deck  40 , which is a rectangle planar plate with a same area as the upper metal plate  30  and plural nipples  42  disposed on the top surface thereof for serving as a mounting foundation, has plural fixing holes  41  created in a pair of longitudinal margins thereof to enable automatic threading screws D to pass through to corresponding tucked edges  36  on the upper metal plate  30  for mounting deck  40  and plate  30  to each other; 
         [0048]    The sandwiched adiabatic layer  50 , which is made of materials with an adiabatic property such as foaming isocyanate, volatile polystyrene, wools of mineral dregs, aluminum silicate or the like, is sandwiched between the lower metal plate  20  and deck  40 ; 
         [0049]    The right flank  60 , which covers a right transverse side of the assembled upper metal plate  30  and deck  40 , has an inlet pipe fitting  61  and an outlet pipe fitting  62  configured thereat such that the internal end of the inlet pipe fitting  61  is connected to the inlet duct  23  and the internal end of the outlet pipe fitting  62  is connected to the outlet duct  24 ; and 
         [0050]    The left flank  70 , which covers other left transverse side of the assembled upper metal plate  30  and deck  40 , has the same area and shape as those of the right flank  60 . 
         [0051]    Again, in this embodiment, two parallel comb-like groove sets  37  may be arranged in interlaced juxtaposition on the top surface  31  of the upper metal plate  30  such that every adjacent prong in each of the groove sets  37  is separated by an even number of rows, for example four rows, of the frustoconical indentations  33  (as shown in  FIG. 17 ) so that all prong grooves in each of the groove sets  37  are interlaced in such a manner as to enhance the directionality of water circulation in the hollow space  35  with a resulting increase in the efficiency of the heat exchange. 
         [0052]      FIG. 17  through  FIG. 19  show the installation and operation of a heat exchanger for a bathing shower according to the second embodiment of the present invention. For installation, a tap water pipe P is connected to the inlet pipe fitting  61  of the right flank  60 , and an inlet pipe  101  of a water heater  100  is connected to the outlet pipe fitting  62  of the right flank  60  to finish the installation. For shower operation, hot shower water W comes from the water heater  100  via outlet pipe  102  and exits the shower sprayer  103  for showering on the user&#39;s body, after which the hot shower water W drips to the top surface  31  of the upper metal plate  30 . Then, cold tap water W 1 , which comes from the tap water pipe P via the inlet pipe fitting  61  of the right flank  60  and flows into the hollow space  35  enclosed by the bottom surface  32  of the upper metal plate  30  and the lower metal plate  20  via the inlet duct  23  and water intake  21  of the lower metal plate  20 , performs heat exchange by absorbing thermal energy of the hot shower water W that has already dripped to the top surface  31  of the upper metal plate  30  (as shown in  FIG. 19 ). The cold tap water W 1  thus becomes warm heat-exchanged water W 2  as a result of the heat exchange and flows into the inlet pipe  101  of the water heater  100  via the outlet pipe fitting  62  of the right flank  60  to save heating energy consumption by the water heater  100  (as shown in  FIG. 17 ). Finally, the waste hot shower water W, which has been heat exchanged, is discharged out of an outlet duct  24  via a water outtake  22  in the lower metal plate  20  (as shown in  FIG. 18 ). 
         [0053]    Because of the adiabatic feature of the sandwiched adiabatic layer  50 , the temperature of the warm heat-exchanged water W 2  can be well maintained by the sandwiched adiabatic layer  50  so that minimal thermal energy of the warm heat-exchanged water W 2  to the inlet pipe  101  of the water heater  100  will be lost. Moreover, the heat exchanging effect will be increased due to enhancement of the water circulating direction in the hollow space  35  by the two parallel comb-like groove sets  37  juxtaposition on the top surface  31  of the upper metal plate  30 . Thus, the overall energy saving effect for the water heater  100  is substantially enhanced by the heat exchanger of the present invention. Furthermore, because of the supporting effect resulting from the indentation bottom  34  of each frustoconical indentation  33  in the upper metal plate  30  being closely attached to the lower metal plate  20 , the heat exchanger assembly is strong enough to bear the body weight of the shower user without any deformation so that application safety is well provided. 
         [0054]      FIGS. 20 through 24  show a heat exchanger for a bathing shower according to a third embodiment of the present invention. The heat exchanger for a bathing shower in this embodiment includes a top metal plate  80 , a metal tubular array  90 , a sandwiched adiabatic layer  50 , a deck  40 , a right flank  60  and a left flank  70 , wherein: 
         [0055]    The top metal plate  80 , which is a rectangular cambered plate made of a non-magnetic corrosion-resistant metal by a stamp-shaping process, has a top surface  81 , a bottom surface  82 , two transverse sides  83  and two longitudinal sides  84  with a pair of longitudinal tucked edges  85 ; 
         [0056]    The metal tubular array  90 , which is located beneath and attached to the bottom surface  82  of the top metal plate  80 , includes a plurality of (8) straight metal tubes  91 , a plurality of (left 4 and right 3) U-bend fittings  92 , and two offset fittings  93 , wherein the straight metal tubes  91 , each of whose section shape is square, are abutted in order from frontmost to backmost, and referred to in the following description (but not in the drawings) as tubes  91 - 1 , - - - , and  91 - 8 ; 
         [0057]    Each U-bend fitting  92 , which is a bent hollow tube with a pair of parallel square projections  921  configured at each open end respectively such that an outer size of each square projection  921  is slightly smaller than an inner size of each of the straight metal tubes  91 , with the U-bend fittings  92  being referred to in the following description (but not the drawings) as  92 - a , - - - , and  92 - g  in order from left-front corner to right-back corner via left-back corner and right-front corner; 
         [0058]    Each of the offset fittings  93  has a square projection  931  disposed at an internal open end for connection to an open square end of the straight metal tubes  91  while a pipe fitting projection  932  is disposed at an external open end for connection to the inlet pipe fitting  61  or outlet pipe fitting  62  in the right flank  60 ; 
         [0059]    By a suitable interlaced coupling arrangement of the plural straight metal tubes  91  and plural U-bend fittings  92  (for example, in which U-bend fitting  92 - a  couples each left end of straight metal tube  91 - 1  and straight metal tube  91 - 2  while U-bend fitting  92 - e  couples each right end of straight metal tube  91 - 2  and straight metal tube  91 - 3 , and so on), a continuous water circulating passage  94  can be created in the metal tubular array  90  (as shown in  FIG. 24 ); 
         [0060]    The deck  40 , which is a rectangular planar plate with a same area as the top metal plate  80  and plural nipples  42  disposed on the top surface thereof for serving as a mounting foundation, has plural fixing holes  41  created in a pair of longitudinal margins thereof to receive automatic threading screws D that extend through to corresponding pair tucked edges  85  on the top metal plate  80  for screw mounting the deck  40  to the top metal plate  80 ; 
         [0061]    The sandwiched adiabatic layer  50 , which is made of materials with an adiabatic property such as foaming isocyanate, volatile polystyrene, wools of mineral dregs or aluminum silicate and the like, is sandwiched between the metal tubular array  90  and deck  40 ; 
         [0062]    The right flank  60 , which covers a right transverse side of the assembled top metal plate  80  and deck  40 , has an inlet pipe fitting  61  and an outlet pipe fitting  62  configured thereat such that the internal end of the inlet pipe fitting  61  is connected to a pipe fitting projection  932  of an offset fitting  93  and the internal end of the outlet pipe fitting  62  is connected to a pipe fitting projection  932  of the other offset fitting  93  (as shown in  FIG. 23 ); and 
         [0063]    The left flank  70 , which covers the other left transverse side of the assembled top metal plate  80  and deck  40 , has the same area and shape as those of the right flank  60 . 
         [0064]    In this embodiment, all the square section shapes for the end section of each straight metal tube  91 , the square fitting projection  921  of each U-bend fitting  92 , and the square fitting projection  931  of each offset fitting  93  in the metal tubular array  90  can be altered into elliptic section shapes to adapt to elliptic straight metal tubes  95  (as shown in  FIG. 25 ), elliptic fitting projections  961  and elliptic fitting projections  971  (not shown in  FIG. 25 ). 
         [0065]    In practical application, cold tap water W 1  initially flows into the water circulating passage  94  in the metal tubular array  90  via, in order, the inlet pipe fitting  61  of the right flank  60  and connected offset fitting  93 . Second, hot shower water W, after being sprayed onto the user&#39;s body, will drip to the top surface  81  of the top metal plate  80 . Third, the cold tap water W 1  will be heated up to become warm heat-exchanged water W 2  after heat exchanging is carried out by the metal tubular array  90 . Finally, the warm heat-exchanged water W 2  is fed to the inlet pipe  101  of the water heater  100  via, in order, the other offset fitting  93  and connected outlet pipe fitting  62  (as shown in  FIGS. 23 and 24 ) to achieve the effect of heating energy consumption saving for the water heater  100 . Moreover, because of the big section area of the straight metal tube  91  in the metal tubular array  90 , the heat exchanger for a bathing shower in this embodiment of the present invention can be applied in a large scale bathing shower site to supply a sufficient quantity of hot shower water W. Moreover, in addition to the relatively cheap procurement cost of the straight metal tubes  91 , mass production of the U-bend fitting  92  and offset fitting  93  is feasible by means of a molding process. Therefore, the overall manufacturing cost can be substantially reduced without any negative effect on marketing promotion and selling of the heat exchanger for a bathing shower according to the present invention. 
         [0066]    Finally, referring to  FIGS. 26 through 28 , the above-described metal tubular array  90  can be modified into many variant metal tubular arrays  200 , such as either an adapted serpentine configuration extending from both longitudinal margins and symmetrically arranged with respect to a central line beneath the bottom surface  82  of the top metal plate  80  and vice versa (as shown in  FIG. 26 ), or an adapted coil configuration that is wound outwardly from center beneath the bottom surface  82  of the top metal plate  80  and vice versa (as shown in  FIGS. 27 and 28 ). All of these different variations will have a significant effect in reducing energy consumption by the water heater  100 .