Abstract:
Provided is a hot water tank attached to a boiler. Water flows along a buffer tank as well as a hot water coil by providing the buffer tank and the hot water coil in an outer tank. Heat source applies heat water between the outer tank and the buffer tank while flowing therebetween. A significant amount of hot water IS supplied, and the temperature variation of the hot water is reduced.

Description:
BACKGROUND 
       [0001]    The present invention relates to a hot water tank attached to a boiler. In more particular, the present invention relates to a hot water tank attached to a boiler, capable of supplying a significant amount of hot water and reducing the temperature variation of hot water by providing a buffer tank and a hot water coil in an outer tank. 
         [0002]    A hot water tank attached to a boiler temporarily stores and supplies hot water. The hot water tank attached to the boiler is used for various uses including such as office and factory uses, as well as for home uses such as washing-up, taking a bath, and laundering. 
         [0003]    Meanwhile, various types of hot water tanks are disclosed in several references including Korean Patent Registration No. 10-1023505, which is titled “hot-water tank”, and Korean Unexamined Patent Publication No. 2011-0130890 which is titled a hot water storage tank for a water heater. 
         [0004]    However, the above related arts commonly disclose a structure in which a hot water tank includes only a hot water coil, or only a single tank is provided without the hot water coil. 
         [0005]    Accordingly, when only the hot water coil is provided, although water is more rapidly heated, the supply of a significant amount of hot water may not be ensured, and the temperature variation of the hot water may be greatly made. 
         [0006]    In addition, when only the single tank is provided, although a significant amount of hot water is supplied, time to heat water is prolonged, and the temperature variation of hot water is still great in spite of the less temperature variation of the hot water as compared with when only the hot water coil is provided. 
       SUMMARY OF THE INVENTION 
       [0007]    Accordingly, the present invention has been made keeping in mind the above problems occurring in the related art art, and an object of the present invention is to provide a hot water tank attached to a boiler, capable of supplying a significant amount of hot water and reducing the temperature variation of hot water. 
       Technical Solution 
       [0008]    In order to accomplish the objects, there is provided a hot water tank attached to a boiler. The hot water tank includes an outer tank having a space therein, a buffer tank installed at a central axis inside the outer tank to temporarily store and supply hot water, a hot water coil installed between the outer tank and the buffer thank and having a one-side water entrance end linked with an outside through the outer tank and an opposite-side water exit end linked with the buffer tank, a first supply port linked with the one-side water entrance end of the hot water coil, a first discharge port linked with the buffer tank, a second supply port linked with one side of the outer tank to supply heat source to heat water discharged through the first discharge port after the water has been supplied through the first supply port, and a second discharge port linked with an opposite side of the outer tank to discharge the heat source supplied to the second supply port. 
         [0009]    Preferably, city water or pre-heated water is supplied to the first supply port, and the hot water heated by the heat source is discharged through the first discharge port. 
         [0010]    Preferably, the heat source is water heated by the boiler, the heated source is supplied to the second supply port, and heating circulation water discharged from the second discharge port is collected to the boiler. 
         [0011]    Preferably, both upper and lower end portions of the buffer tank or both left and right end portions of the buffer tank are exposed out of the outer tank, and the first discharge port is provided in a portion of the buffer tank exposed to the outside. 
       Advantageous Effects 
       [0012]    As described above, according to the present invention, water flows along the buffer tank as well as the hot water coil by providing the buffer tank and the hot water coil in the outer tank. In this case, heat source applies heat between the outer tank and the buffer tank while flowing therebetween. Accordingly, a significant amount of hot water can be supplied, and the temperature variation of the hot water can be reduced. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0013]      FIG. 1  is a perspective view showing a hot water tank attached to a boiler according to the present invention. 
           [0014]      FIG. 2  is a sectional view showing the hot water tank attached to the boiler according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0015]    Hereinafter, a hot water tank attached to a boiler according to an exemplary embodiment of the present invention will be described in detail with reference to accompanying drawings. 
         [0016]    As shown in  FIGS. 1 and 2 , a hot water tank attached to a boiler according to the present invention includes an outer tank  110 , a buffer tank  120 , a hot water coil  130 , a first supply port  141 , a first discharge port  142 , a second supply port  151 , and a second discharge port  152 . 
         [0017]    The outer tank  110  includes a sealed tank having a space therein. Although  FIGS. 1 and 2  show an oval-type tank having a vertically long length as an example, a tank having a horizontally long length may be used. 
         [0018]    The buffer tank  120  is installed at the central axis inside the outer tank  110  to temporarily store and supply hot water. The buffer tank  120  may include an oval-type tank having a vertically long length or a horizontally long length depending on the shape of the outer tank  110 . 
         [0019]    In particular, as shown in drawings, when the buffer tank  120  has the vertically long length, both upper and lower end portions of the oval-type tank may be exposed out of the outer tank  110 , so that the first discharge port  142  may be inconveniently provided. 
         [0020]    If the entire portion of the buffer tank  120  is embedded in the outer tank  110 , a work of providing the first discharge port  142  must be performed in the outer tank  110 . In this case, the manufacturing of the hot water tank may be difficult. 
         [0021]    Meanwhile, although not shown in drawings, if the outer tank  110  has the horizontally long length so that the buffer tank  120  has the horizontally long length, both left and right end portions of the buffer tank  120  may be exposed out of the outer tank  110 . 
         [0022]    The hot water coil  130  is installed to increase a heat exchange area so that hot water may be rapidly supplied in sufficient amount. The hot water coil  130  is installed in an empty space provided between the outer tank  110  and the buffer tank  120 . 
         [0023]    The hot water coil  130  is installed outside the buffer tank  120 . The hot water coil  130  includes a stainless pipe wound around the buffer tank  120  several times in a longitudinal direction of the hot water tank. 
         [0024]    In addition, one water entrance end of the hot water coil  130  is linked with an outside through the outer tank  110 , and an opposite water exit end of the hot water coil  130  is linked with the buffer tank  120 . In  FIG. 2 , for example, the opposite water exit end of the hot water coil  130  is linked with a lower end portion of the buffer tank  120 . 
         [0025]    Accordingly, water supplied through the water entrance end is supplied to the buffer tank  120  after passing through the hot water coil  130 , and water temporarily stored in the buffer tank  120  is discharged through the first discharge port  142 . In this case, as described later, since the water is heated through a heat exchange scheme, hot water is supplied through the first discharge port  142 . 
         [0026]    The first supply port  141  is linked with the water entrance end of the hot water coil  130 . For example, the first supply port  141  is linked with the water entrance end of the hot water coil  130  provided at the upper portion of the outer tank  110 . 
         [0027]    The water supplied to the first supply port  141  is representatively city water supplied through a water pipe. 
         [0028]    However, recently, since city water is pre-heated by collecting heat wasted when driving the boiler (or heat pump) in order to save energy, the water includes pre-heated water. 
         [0029]    The first discharge port  142  is linked with the buffer tank  120 . For example, an upper portion of the buffer tank  120  is partially exposed out of the outer tank  110 , and the first discharge port  142  is provided in the exposed upper portion of the buffer tank  120 . Therefore, as described above, the hot water tank is easily manufactured. 
         [0030]    The second supply port  151  is linked with one side of the outer tank  110 , and the second discharge port  152  is linked with an opposite side of the outer tank  110 . Accordingly, the heat source supplied to the second supply port  151  is discharged through the second discharge port  152  after flowing the space between the outer tank  110  and the buffer tank  120 . 
         [0031]    According to the present invention, the city water or the pre-heated water sequentially passes through the first supply port  141 , the hot water coil  130 , the buffer tank  120 , and the first discharge port  142 . After the heat source has been supplied to the second supply port  151 , the heat source is discharged through the second discharge port  152 . 
         [0032]    Therefore, since the heat source and the city water (or pre-heated water) exchange heat, hot water may be supplied. In this regard, the hot water tank according to the present invention may serve as a kind of an indirect heat exchanger. 
         [0033]    Meanwhile, the heat source representatively includes water heated by the boiler. The high-temperature water heated by the boiler is supplied to the second supply port  151 . The high-temperature water is generated by heating the city water or the pre-heated water. 
         [0034]    Heating circulation water having the temperature lowered after the heat exchange has been finished is discharged through the second discharge port  152 , and the discharged heating circulation water is collected to the boiler (that is, the heated water returns). To this end, the hot water tank according to the present invention is attached to the boiler. 
         [0035]    The heated water is not supplied to the hot water tank according to the present invention in heating. On the contrary, the hot water is supplied to the hot water tank to the extent that the hot water is used or the condition for the heating cost is satisfied. However, if the temperature of the hot water is excessively lowered after monitoring the temperature of the hot water tank, the hot water may be temporarily supplied to the hot water tank even under heating. 
         [0036]    As described above, according to the present invention, since the city water or the pre-heated water is directly heated by using the heated water, the water filled in the hot water tank is maintained at a suitable temperature. Therefore, the supply of a sufficient amount of hot water can be ensured, and the temperature variation of the hot water can be minimized. 
         [0037]    Although the exemplary embodiments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary embodiments but various changes and modifications can be made by one ordinary skilled in the art without changing of the subject matter of the present invention. 
         [0038]    Accordingly, the described embodiments are provided for illustrative purpose in order to make those skilled in the art completely comprehend the scope of the present invention. The present invention is defined by the spirit and scope of claims hereinafter claimed.