Abstract:
A medical sanitary multifunctional system bed is provided for nursing, having necessary functions that can be added optionally according to clinical conditions of users. The optional addition of functions allows the medical sanitary multifunctional system bed to perform necessary functions, on a case-by-case basis, thereby minimizing the economic burden imposed on patients. Ordinarily, the bed includes a lower capsule, supported by a metallic support frame, an upper capsule mounted on the lower capsule, a movable and rotatable portion, which is supported by the metallic support frame, and a plurality of removable cushions placed on the movable portion. On a optional basis, the bed may include a stool, a bathtub, a shower, and additional washers.

Description:
BACKGROUND OF THE INVENTION 
   Description of the Prior Art 
   As widely known, there is a need for nursing and for attending to persons when such persons suffer from diseases or become too serious in condition to move about freely. To respond to this need, beds for nursing have been provided substantially with convenient functions for facilitating the nursing of patients. Representative functions so far developed for nursing beds are, for example, frame bodies that are used for fixing patients to help them turn on their sides in bed, tables used for meals, toilets to be set under the bed frame, and washing facilities or the like. Shower sets and bath sets are also functions that are very helpful for patients who are so feeble as to be confined to bed. 
   However, unfortunately, nursing beds having such convenient functions have been very costly unavoidably, because such beds are produced only in small lots, and furthermore, prices for such beds inevitably become higher in order to accommodate the types of functions included. Hence, as more functions are provided, such nursing beds often become so high in price that they cannot be purchased by those who truly wish to use them. 
   It should be noted that clinical conditions vary widely among patients in need of nursing beds and, in most cases, the functions needed are different among individuals. However, in conventional nursing beds, the types of functions included cannot be specified in detail, and desired functions cannot be used unless functions that are not needed to be used are paid for as well. 
   For example, a toilet set that is disposed underneath the bed is not needed before a patient becomes confined to bed, and such a function is unnecessary for patients who are able to walk to the toilet. Likewise, shower sets, bath sets and the like are sure to provide useful functions, however, at present, such functions are purchased considering their expected use at some point in the future, rather than based on a need for current use. Thus, up to the present, in some cases, payments even for unnecessary functions must be made, however reluctantly. 
   SUMMARY OF THE INVENTION 
   The present invention has been made in light of the problems mentioned above, wherein an object of the invention is to provide a nursing bed in which all necessary functions therefor are made available by adding such functions in a modular fashion, in accordance with the clinical conditions of the patient, thereby enabling the bed to be provided at the lowest possible cost. 
   The above object of the present invention is achieved by a medical sanitary multifunctional system bed, which provides various functions that are effective for the nursing of patients whose own bodies cannot move easily and freely, such as fairly aged persons who are so feeble as to be confined to bed and the like. The multifunctional system bed comprises a body, which is constituted of a lower bed portion for supporting the lower half body of a user, a waist bed portion for supporting the center part of the user, and an upper half body supporting upper bed portion for supporting the upper half body of the user. The body of the bed is rotatably mounted on a bed base, and is arranged so as to allow the mounting of an upper hot water washer at the upper bed portion for supporting the upper half body, as well as mounting of a lower hot water washer and a lower flush toilet to be disposed under the waist bed portion, and mounting of an upper half body support member, which is used for changing the position of the user on the upper half body supporting bed portion. 
   On the other hand, a part of the bed cushion, which is disposed at the waist bed portion, is removable, so that the lower hot water washer and the lower flush toilet can be exposed to enable full use of the flush toilet. 
   The medical sanitary multifunctional system bed has several other features. The flush toilet may include a crushing means, comprising a crushing cutter and a motor, serving as a crushing means for crushing and discharging excrement from the user. Further, the body of the bed is rotatably mounted through a rotating support shaft, and is made rotatable by a specified angle in a specified direction, by means of a rotation controller. Still further, a water tank is provided to store hot water, which is supplied to the upper and lower hot water washers, while a cord heater is wound around a hose for the supply of hot water, wherein the hot water stored in the water tank is supplied thereby to the upper and lower hot water washers. 
   As a result of the techniques and means of the present invention, as mentioned above, it is possible to provide a bed for nursing, which has only those functions that are needed for patients and fairly aged persons who use the bed, and thus the bed itself can be supplied at a lower cost. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a general plan view showing an embodiment according to the present invention. 
       FIG. 2  is a view illustrating a portion P of the view shown in  FIG. 1 . 
       FIG. 3  is a perspective view showing an example of a bed base. 
       FIG. 4  is a sectional view showing an example of a lower flush toilet to be disposed under a waist bed portion. 
       FIG. 5  is a sectional view showing an example of a water tank. 
       FIG. 6  is a view showing an example of the waist bed portion properly changed in form. 
       FIG. 7  is another view showing an example of the waist bed portion properly changed in form. 
       FIG. 8  is a view showing an example of an upper lid body portion properly changed in form. 
       FIG. 9  is a view showing an example of a lower bed portion properly changed in form. 
       FIG. 10  is another view showing an example of the lower bed portion properly changed in form. 
       FIG. 11  is a perspective view showing another example of the upper lid body portion properly changed in form. 
       FIG. 12  is a view showing an example of the overall bed properly changed in form. 
       FIG. 13  is a view showing an example of using a body support frame. 
       FIG. 14  is a perspective view showing another example of the upper lid body portion properly changed in form. 
       FIG. 15  is a perspective view showing an example of the medical sanitary system bed made up of a convenient bed type, which is housed in a water tank. 
       FIG. 16  is a view showing an example of the convenient bed type housed in the water tank. 
       FIG. 17(F)  is a perspective view of the medical sanitary multifunctional system bed, illustrating an embodiment according to the present invention. 
       FIGS. 17(A) ,  17 (B) and  17 (E) are partial views, illustrating states in which the body of the bed and a tray for transferring a patient or the like are transferred relatively, according the present invention. 
       FIGS. 17(C) and 17(D)  are further partial views, illustrating states in which the body of the bed and the tray for transferring a patient or the like are transferred relatively, according to the present invention. 
       FIG. 18(A)  is an enlarged view of the right side of the view shown in  FIG. 17  (C). 
       FIG. 18(B)  is a view for describing the front of the view shown in  FIG. 18  (A). 
       FIG. 19  is a perspective view illustrating a state in which a patient is given a meal, wherein a mobile type upper washer is shown on the left. 
       FIG. 20  is a perspective view illustrating the state in which a patient is sleeping, in which a rotation controller is shown in operation for preventing bed sores. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Preferred embodiments according to the present invention shall be described in detail below, with reference to accompanying drawings. 
   Referring first to  FIG. 1 ,  FIG. 2  and  FIG. 3 , two hinge holes  34  for rotatably supporting a rotation support shaft  2  are provided vertically at each of center parts on both sides of a bed base  1 . A hinge  34   a  is mounted on the hinge holes  34 , wherein a rotation controller  4  is provided for the hinge  34   a . The body  3  of the bed is mounted on the bed base  1 . In the following embodiments, the rotation controller  4  comprises a motor, wherein a reduction gear or the like is provided to accomplish rotation of the body  3  of the bed, without requiring application of large forces. The position of the rotation controller  4  mounted on the hinge  34   a  can be selected vertically, thereby allowing the height position of the body  3  of the bed to be set freely. For example, the position may be lowered during normal operations, and during use of the flush toilet, the position of the bed may be raised for the user confined to the bed, thereby significantly improving the handling of the body  3  of the bed. 
   In the disclosed embodiments, the bed base  1  is provided with a string-hoisted bed portion  5 , a waist bed portion  6 , an upper half body supporting bed portion  7 , and the like, wherein the waist bed portion  6  and the string-hoisted bed portion  5  are made foldable mutually, and connected with a bed connection cover  8 , which prevents the user&#39;s body from getting caught in the folded portion when the string-hoisted bed portion  5  is lifted or lowered. In  FIG. 1 , the string-hoisted bed portion  5  and the waist bed portion  6 , which are shown as forming a zone P, are divided to enable the lower half body of the user to be washed, as illustrated by a side view of  FIG. 2 . A lower water tank  21 , an upper lid body  22 , a hoisting string  23 , a hoisting motor  24 , with a string for lifting or lowering the string-hoisted bed portion  5 , and the like, are also provided. Several drainage holes  5   a  also are formed in the string-hoisted bed portion  5 . 
   As shown in  FIG. 2 , a cord heater  25  is arranged for the cushion  60  of the waist bed portion  6 , for keeping the user  10  moderately warm, so that the body of the user  10 , after becoming wetted under washing, can be dried completely. An air heater  220  is mounted on an upper lid body  22 , to enable the body, after becoming wetted by use of an upper hot water washer  26 , to be dried. The cushion  60  of the bed also can be dried by the above-mentioned methods and, for example, the cushion  60  may be freely detachable, through use of Velcro or the like, thereby enabling quick replacement of a wet cushion  60  with a dry one. 
   An upper hot water washer  26  is mounted on the upper lid body  22 , and a lower hot water washer  27  is mounted below the position of the hip of the user  10 . In the disclosed embodiments, an example of a one-side opened arrangement of the cushion is shown. The body of the user  10  is washed by discharging hot water onto the user  10 , in a shower, from the upper and lower hot water washers  26  and  27 . A water shielding cover  28  is mounted at an end part of the upper lid body  22 , to prevent hot water from scattering over the upper half body of the user  10 , while the lower half body is being washed. The water shielding cover  28  is formed out of a rubber or a vinyl-based synthetic resin. In  FIG. 2 , an example is shown of a cord heater-applied belly-band  11 , which is mounted on the belly of the user  10 , to keep the user  10  warm while shielding the belly portion of the user from water. In order to support the body of the user  10  while the lower portion is opened, as shown, a waist support belt  29  is disposed on the waist bed portion  6  of the bed. 
   To drain the water that has accumulated in the bottom part of the lower water tank  21 , an underwater pump  21   a  is provided. Accordingly, when hot water discharged onto the user  10  from the upper hot water washer  26  accumulates in the lower water tank  21 , the water is pumped and drained via an underwater pump  21   a , to prevent overflowing of water from the lower water tank  21 , which might otherwise cause the inside of the room where the bed is placed to become wet. 
   As shown in  FIG. 1 , a plurality of upper bed washing nozzles  9  are arranged for washing portions between the user  10  and the waist bed portion  6 . None of these need to be used, except when the user  10  becomes so feeble as to be confined to bed. 
   Both on the left and right sides of the upper half body supporting bed portion  7 , upper half body supporting structures  12  and  13  are disposed, which are slidable to approach each other, so as to match the size of the user  10 . When the upper half body supporting structures  12  and  13  are used in accordance with the present embodiment, the upper half body supporting structures  12  and  13  are fixed at specified positions determined to match the width of the body. Then, with a blanket or the like thereon, the user  10  is fastened onto the bed with a belt so that the user  10  is supported and kept from falling from the bed when the bed is inclined, to prevent possible bedsores from occurring. 
   Various types of beds may be considered, one example of which is shown in  FIG. 3 . As illustrated in  FIG. 3 , the bed base  1  has casters  31 , mounted at a lower part thereof, for facilitating movement of the bed. 
   As previously stated, upper and lower vertical plates  32  and  33  are provided respectively with hinge holes  34 , which are used for moving the rotating support shaft  2  vertically when the bed is rotated. A lock hole  35  for fixing the bed is formed in the upper vertical plate  32 . An auxiliary bed portion  36  is attached on one side, along the length of the bed base  1 , in order to increase the effective bed width when the bed is not rotated. 
   Referring to  FIG. 4 , a lower flush toilet  400  shall be described. The lower flush toilet  400  is disposed under the waist bed portion  6  of the bed, as shown in  FIG. 1 . At the lower end part thereof, a rotary roller  400   a  is disposed within an engaging part  6   a  provided on the waist bed portion  6 , in order to guide the lower flush toilet  400  to a specified position underneath the waist bed portion  6 . 
   On the other hand, casters  401  for facilitating movement of the lower flush toilet  400  are disposed on the underside of a base plate  402 , which is provided at a lower part of the lower flush toilet  400 , in order to allow it to be pulled out easily from underneath the waist bed portion  6  during cleaning or repairing. A support base  403  is mounted on the base plate  402  through an air support mechanism  404 , which is provided to support the weight of an upper washing water tank  405  when the tank  405  is filled with water. In the present embodiment, the air support mechanism is illustrated as being constituted of a bellows  404   a  and a compressor  404   b.    
   A ball tap  406  is mounted in the washing water tank  405 , which moves vertically depending on washing water stored in the washing water tank  405 , so that water is supplied into the washing water tank  405  from a water supply pipe according to the position thereof. The washing water stored in the washing water tank  405  is pumped using an underwater pump  407 , so as to be supplied into the lower hot water washer  27 . 
   On the other hand, a crushing chamber  408  is provided, which receives the hot water discharged from the lower hot water washer  27 , together with excrement discharged from the user  10 . A crushing cutter  409  is disposed to crush solid matter while the solid matter is rotated by the motor  410  of the crushing chamber  408 . Filth that is crushed by the crushing cutter  409  is accumulated in a sewage chamber  412 , wherein the filth passes through a dirt filter  411  disposed at a lower end portion of the crushing chamber  408 . When the liquid in the sewage chamber  412  reaches a specified level, the level is detected by a float switch  413 . More specifically, when the float switch  413  detects that the level has reached the specified level, an underwater pump  414  is activated to discharge the sewage to the outside. 
   Referring to  FIG. 5 , a water tank  500  shall be described. The water tank  500  in accordance with the present embodiments is built of a resin or steel material, and includes a cold water layer  501  and a hot water layer  502 . Ball taps  503  and  504  are arranged respectively in the cold water layer  501  and the hot water layer  502 , which restrict the cold water and the hot water supplied through water resistant hoses  505  and  506  so as to reach specified levels. Underwater pumps  507  and  508  are arranged respectively in the cold water layer  501  and the hot water layer  502 . The underwater pump  507  in the cold water layer  501  supplies cold water to the lower flush toilet  400  through a hose  509 , so that the cold water may be used for washing the accumulated filth. Hot water, which is pumped by the underwater pump  508 , is supplied to the hot water washers  26  and  27  through a hose  510  that supplies the hot water. According to the present embodiments, utilization of hot water is handled separately from the utilization of cold water, in order to prevent useless consumption of hot water, thereby reducing required expenses. The underwater pump  508  disposed in the hot water layer  502  supplies the hot water to the upper and lower hot water washers  26  and  27  through the hot water supply hose  510 , which is wound with a cord heater. In the present embodiments, a heat insulating material is arranged on the wall surfaces of the hot water layer  502 , while hot water is supplied through the hot water supply hose  510  that is wound with the cord heater, so that the hot water is prevented from cooling while inside the hot water supply hose  510 . 
   Thus, hot water can be supplied while being kept hot constantly during operation, to prevent problems caused by cooling of the hot water while inside the hot water supply hose  510 , when hot water is supplied to the user  10 . 
   Referring to  FIG. 6 , an example of the waist bed portion  6 , shown properly changed in form, shall be described. A waist bed  600  is arranged with cushions  601  and  602  that open both to the left and right. Opening or closing of the cushions  601  and  602  is performed by an opening-closing control string  603 , which is pulled by rotation of a motor (not illustrated), in order to move the cushions to a normal position, at which the user lies on his side, or to a position in which the cushions serve as a toilet seat for discharging excrement. To wash the surfaces of the cushions  601  and  602 , hot water pipes  604  are arranged along both left and right sides thereof, and hot water flowing out of the hot water pipes  604  runs along the surfaces of the left and right cushions  601  and  602 , as indicated by the dotted lines in  FIG. 6 . The cushions  601  and  602  are constructed by placing the cushions, which may contain a heater for warming the cushions, on a stainless plate or a hard synthetic resin. In the example shown in  FIG. 6 , a lower washer  606  is arranged in a divided form, on left and right sides of a crushing chamber  605 . Hot water, which is discharged from the lower washer  606  and washes the user, is guided into the crushing chamber  605 . 
     FIG. 7  shows another example of the waist bed portion  6 , properly changed in form. A waist bed  700  has left and right cushions  701  and  702  arranged on the left and right areas thereof, and a body waist/hip cushion  703  is disposed between the left and right cushions  701  and  702 . The body waist/hip cushion  703  is formed into a shape that supports the hip portion of the user  10  when the user sits thereon. The body waist/hip cushion  703  is further cut off at a central part thereof, in order to facilitate washing of localized portions of the user&#39;s body, by hot water discharged from the lower hot water washer  27 . 
   Referring to  FIG. 8 , an example of the upper lid body  22 , properly changed in form, shall be described.  FIG. 8  shows an example in which an upper lid body  800  comprises a capsule formed in a semicircle, which surrounds the waist portion of the user  10  who is arranged on the bed  802 . The bed  802  is built higher than a central part thereof on both sides, so that water dropped onto the bed gathers in the central part, and runs downward from the central part. 
     FIG. 9  shows an example of the lower part of the string-hoisting bed  5 , properly changed in form. As shown in  FIG. 9 , in the present example curtains  901  and  902  for preventing scattering of water are disposed on both left and right sides on the underside of a bed  900 . The curtains  901  and  902  are detachably mounted on protruded pieces  903  and  904 , which project downwardly from both left and right sides on the underside of the bed  900 , through fasteners  905  and  906 . The curtains  901  and  902  can be removed freely, for cleaning under the bed  900 . 
   Strings  907  are mounted respectively at lower end parts of the curtains  901  and  902 , in order to regulate the interval between the curtains  901  and  902  using the strings  907 , while preventing the curtains  901  and  902  from becoming stuck on or adhered to the lower water tank  21 . 
     FIG. 10  shows an example of a connection between a bed  1000  and the lower water tank  21  (not illustrated). In this example, a bellows type curtain  1001 , for preventing the scattering of water, is disposed on the underside of the bed  1000 . In the case of the present example, water dropping from the bed  1000  is prevented from scattering into the room, and is gathered accurately and efficiently in the lower water tank  21 . 
   Referring to  FIG. 11 , an example of the upper lid body  22 , properly changed in form, shall be described. According to the present example, an upper lid body  1100  comprises a box-like framework  1101 , built of steel or the like, and a transparent body  1102  made of a synthetic resin disposed thereon. One side end of the transparent body  1102  is mounted on the bed through a hinge mechanism (not illustrated), while a knob  1103  is mounted on the other side end thereof, which is used for opening and closing of the transparent body. 
     FIG. 12  is a perspective view showing the example of the upper half body supporting bed portion. In the example shown in  FIG. 12 , rails  1201  are installed respectively on front and rear sides of a bed  1200  across the width thereof, and sliders  1202  are slidably disposed on the respective rails  1201 . Body supporting frames  1203  are mounted on the sliders  1202 , while an upper washer  1204  is mounted on the bed  200 . 
     FIG. 13  is a view for describing how the body supporting frames  1203  are used. As shown in  FIG. 13 , the body supporting frames  1203  are slid to contact the user  10  sufficiently. As mentioned above, the body supporting frames  1203  sufficiently contact the user  10  so as to firmly support the user  10  when the bed  1200  is inclined, in order to help the user turn on his or her side while in bed. In  FIG. 13 , numeral  1205  indicates a blanket and numeral  1206  indicates a body supporting belt. 
     FIG. 14  is a perspective view showing another arrangement of the upper lid body  22 . An upper lid body  1400  is constituted of first and second upper lid bodies  1401  and  1403 , which are openably mounted separately on side parts of a bed  1403 . In this manner, division of the upper lid body into the first and second upper lid bodies  1401  and  1403  simplifies the handling thereof, as compared with an integral formation. 
   With reference to  FIGS. 15 and 16 , an example of a convenient type of bed shall be described. As illustrated, in the present example, the convenient bed type  1500  is housed in a water tank  1600 . The convenient bed type  1500  comprises a bed  1501  for supporting the upper half body, a bed  1502  for supporting the waist portion of the body, and a bed  1503  for supporting the user&#39;s legs, each of which are foldable freely individually. 
   The water tank  1600  is rotatably supported on a support base  1700 , and a turning mechanism  1701  (a motor  1701  is shown representing the turning mechanism in  FIG. 16 ) is actuated to turn the water tank so as to be positionable at arbitrary angles. A lower flush toilet  1504 , as mentioned above, is disposed below the bed  1502  that supports the waist portion of the user. The bed  1503  can be set at arbitrary angles using a hoisting mechanism  1505 . In addition, an underwater pump  1601  is arranged within the water tank  1600 , to discharge the sewage accumulated in the water tank  1600  to the outside. 
   In the medical sanitary multifunctional system bed of the present invention, as previously stated, a unique structure is provided, whereby various functions may be added separately onto the body of the bed. Therefore, the user can select necessary functions, in a modular fashion, for constructing the bed, in which functions truly required are arranged systematically. Such a structure eliminates the disadvantage in which the user must pay extra payments at unreasonably higher prices, as a result of including functions which are not actually necessary. 
   For example, the lower flush toilet may be attached under the bed, for use when the user becomes too feeble to walk to the toilet from the bed. In contrast, users who are able to walk to the toilet can obtain system beds at a lower price, which can be lowered by a cost equivalent to that of the lower flush toilet  400 . In order to be attached in a modular fashion, the flush toilet is constructed detachably underneath the bed, hence offering the advantage of facilitating cleaning and maintenance thereof. 
   In addition to the flush toilet underneath the bed, additional functions, which may be made available as needed according to the present invention, are an upper body washer, a bed rotation aid for preventing possible bedsores, shower and bath sets, and the like. The system bed, if provided integrally with all of these functions, would be very costly. However, by selectively adding necessary functions, as in the case of the system bed in accordance with the present embodiments, it is possible to obtain a system bed having necessary functions at reduced cost. 
     FIGS. 17(A) through 17(F)  illustrate an example of the present invention, which enables taking a bath, and how to take a bath. Description is made in order from  FIG. 17(A)  to  FIG. 17(F) . Numeral  53  in  FIG. 17(A)  indicates a cushion part of the bed, on the outside of which a frame (not illustrated) made from wood, aluminum, steel or the like, is applied. The cushion parts of the bed are turned with a hinge  52 , and are automatically controlled thereby. Rails, indicated at  51 , are arranged side by side in parallel on the front and rear sides of the frame of the rotary bed, and a gear and lock mechanism are provided within a rotation fixing device, indicated at  50 . 
   A bath tray, indicated at  55 , is normally folded under the body of the bed, so as not to disturb use of the body  53  portion of the bed, and is moved only when the patient requires bathing. The bath tray  55 , as shown in  FIG. 17(A) , is moved to the position indicated in  FIG. 17(B)  when turned by 225 degrees with the rotation fixing device  50 . The bath tray, at the position as indicated in  FIG. 17(B) , is then pushed manually by an attending person using a knob, indicated at  56 , whereby the bath tray is shifted to the position indicated in  FIG. 17(C) . The rotation fixing device is locked in place, and a cushion, such as a Japanese style cushion, is placed beneath the patient  63 , while the patient is lifted slightly so that belts  61  and  62  may be passed around the patient, and then the body of the patient is fixed in place using a belt winding device, indicated at  59 , which may be operable manually or electrically. 
   When the rotation fixing device  50  in  FIG. 17(D)  is unlocked, and the bath tray is transferred toward the ends of the rails, the user&#39;s body and the bath tray reach the position indicated in  FIG. 17(E) . As the bed is turned slowly by 90 degrees with the bed rotation controller  65  shown in  FIG. 17(F) , the bath tray enters into the bath tub and hot water flows thereinto through numerous holes (50 or the like), so as to cover the bath tray. Then, the belts are taken off of the patient, so that the patient may freely take a bath. Thus, the present invention facilitates care of the patient before and during bathing. After completing the bath, the patient is transferred back onto the upper portion of the bed, by following a reverse procedure to the one mentioned above. 
   According to the present invention, the body of the bed is constructed of a lower half body supporting bed portion for supporting the lower half body of the user, a waist-bed portion for supporting the central part of the user, and an upper half body supporting portion for supporting the upper half body of the user. The bed is rotatably mounted on the bed base while being arranged to allow mounting of the upper hot water washer at an upper portion of the bed, together with mounting of the lower hot water washer and the lower flush toilet underneath the waist-bed portion, and mounting of the upper half support body, which is used for changing the position of the user on the upper half body supporting portion of the bed. Accordingly, it possible to provide a bed with functions tailored to the actual needs of the user. As a result, a medical sanitary multifunctional system bed, having only those functions that are required by the user can be supplied at lower cost. The optional addition of the necessary functions in a modular fashion allows the construction of medical sanitary multifunctional system beds, which match the clinical conditions of the user. Such features enable nursing beds to be provided, which have the necessary minimal functions required for proper patient care, and which are sufficient for nursing of patients and elderly persons who are unavoidably confined to bed. Furthermore, according to the present invention, a cord heater is wound around the hot water supply hose that supplies hot water stored in the water tank, to avoid supplying hot water which has become cooled to the user during initial operation, thereby allowing the user to be supplied with comfortable hot water constantly.