Abstract:
A mixing device for a tub for supplying to a tub a mixed liquid which has mixed gas and water includes: a 1 st  mixing tub which includes: a chamber with a port which connects to an inlet pipe of the mixed liquid at the top of the chamber, and a cylinder disposed within the chamber and having an upper end opening which connects to an outlet pipe of the mixed liquid and a lower end opening placed in the vicinity of a bottom of the chamber; and a 2 nd  mixing tub connecting to a flow inlet for supplying the mixed liquid to the inside of the tub and including a supply pipe with multiple holes or bores for the flowing out of the mixed liquid to the mixed liquid which has accumulated inside 2 nd  mixing tub.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    This invention is related to a mixing device for a tub which mixes gas and liquid in order to supply a tub. 
         [0003]    2. Description of the Related Art 
         [0004]    The device disclosed in Japanese Patent Laid-open No. 2001-145676 (patent citation 1) is known as a device which mixes gas and liquid in order to supply a tub in which a warm bath effect is obtained for limbs in liquid with dissolved gas such as carbon dioxide. 
         [0005]    The device disclosed in patent citation 1, provides a tub, a jet nozzle which sprays a jet flow to the tub, and an air intake which connects to the jet nozzle through an air flow pipe. 
         [0006]    As a result of this construction, according to the device disclosed in patent citation 1, it is possible to supply liquid which has been mixed with gas to a tub, and it is possible to enhance the effect of a warm bath. 
         [0007]    However, according to the device disclosed in patent citation 1, because there is simply only the supply of gas through the air flow pipe to the liquid which is to be supplied to the tub, it is not possible to mix enough gas. If it is not possible to mix enough gas, the gas from the liquid which was mixed in the tub will immediately flow out. 
       SUMMARY OF THE INVENTION 
       [0008]    This invention has been made to solve at least this sufficiency problem, having as a goal to supply a mixing device for a tub which provides a mixing structure for supplying sufficient gas to liquid which is supplied, in turn, to a tub. 
         [0009]    In a first embodiment, the present invention provides a mixing device for a tub which supplies to a tub a mixed liquid which has mixed gas and water, characterized by comprising: (a) a 1 st  mixing tub comprising: (i) a chamber with a hole which connects to an inlet pipe of the mixed liquid at the top of the chamber, and (ii) a cylinder disposed within the chamber and having an upper end opening which connects to an outlet pipe of the mixed liquid and a lower end opening placed in the vicinity of a bottom of the chamber; (b) a 2 nd  mixing tub connecting to a flow inlet which supplies the mixed liquid to the inside of the tub, said 2 nd  mixing tub comprising a supply pipe with multiple holes or bores (e.g., more than 100 holes or bores arranged substantially or nearly uniformly along the circumference) for the flowing out of the mixed liquid to the mixed liquid which has accumulated inside 2 nd  mixing tub; (c) an intermediate supply path for supplying the mixed liquid to the 2 nd  mixing tub from the 1 st  mixing tub; (d) a supply path for supplying the mixed liquid to the tub from the 2 nd  mixing tub; (e) a recovery circulating path for recovery of the mixed liquid in the tub to the 1 st  mixing tub; (f) a water supply which supplies water to a circulating path which reaches the tub via the 1 st  and 2 nd  mixing tubs from the recovery circulating path; and (g) a gas supply which supplies gas to the circulating path which reaches the tub via the 1 st  and 2 nd  mixing tubs from the recovery circulating path. 
         [0010]    A second embodiment provides an open-closed valve in the intermediate supply path or the 2 nd  mixing tub in the mixing device for a tub in the first embodiment. 
         [0011]    A third embodiment provides, for the mixing device for a tub in the first or second embodiment, a counter flow wall for making collide in the 2 nd  mixing tub water flow of the mixed liquid introduced accumulated in the 2 nd  mixing tub. 
         [0012]    A fourth embodiment has, for the mixing device for a tub in any of the first to third embodiments, the supply pipe connected to the liquid inlet from the intermediate supply path. 
         [0013]    A fifth embodiment has, for the mixing device for a tub in any of the first to third embodiments, the 2 nd  mixing tub provided with a circulating pump, a flow path for flowing the mixed liquid which accumulated in the 2 nd  mixing tub by the circulation pump, and a flow out path for flowing out of the mixed liquid to the 2 nd  mixing tub from the circulation pump, wherein the supply pipe is connected to the flow out path. 
         [0014]    A sixth embodiment, for the mixing device for a tub in any of the first to fifth embodiments, has the supply pipe which supplies to a shower-shape object the mixed liquid to inside the 2 nd  mixing tub through the multiple holes which are immersed with the mixed liquid. 
         [0015]    A seventh embodiment, for the mixing device for a tub in any of the first to fifth embodiments, has the supply path which supplied to a shower-shape object the mixed liquid in the 2 nd  mixing tub through the multiple holes which are disposed above the liquid surface of the mixed liquid. 
         [0016]    A eighth embodiment, for the mixing device for a tub in any of the first to seventh embodiments, has, as the gas that is supplied by the gas supply section, carbon dioxide. 
         [0017]    According to the first embodiment, it is possible to supply a mixture of liquid and gas to a tub. 
         [0018]    According to the second embodiment, there can be promotion of the dissolution of the gas within mixed liquid by providing an open-closed valve in the intermediate supply path. 
         [0019]    According to the third embodiment, it is possible to sufficiently mix and dissolve the gas in the mixed liquid within the 2 nd  mixing tub by providing a counter flow wall for making collide the water flow of the mixed liquid which has accumulated in the 2 nd  mixing tub and inducing the counter flow of the mixed liquid within the 2 nd  mixing tub. 
         [0020]    According to the fourth embodiment, because the supply pipe of the 2 nd  mixing tub is connected to the flow inlet from the intermediate supply path, when supplying the mixed liquid to within the 2 nd  mixing tub, it becomes possible to elevate the dissolution of the gas. 
         [0021]    According to the fifth embodiment, it is possible to further dissolve the gas in the mixed liquid which has accumulated within the 2 nd  mixing tub. 
         [0022]    According to the sixth embodiment, within the 2 nd  mixing tub, because the supply pipe supplies to a shower-shape object the mixed liquid within the 2 nd  mixing tub by means of multiple holes which have been immersed in the mixed liquid, multiple counter flows within the 2 nd  mixing tub are generated, and it becomes possible to elevate the dissolution efficiency of the gas within the 2 nd  mixing tub. 
         [0023]    According to the seventh embodiment, within the 2 nd  mixing tub, because the supply path supplies to a shower-shape object the mixed liquid within the 2 nd  mixing tub by means of multiple holes which are disposed as multiple holes on top of the liquid surface of the mixed liquid, it becomes possible to elevate the dissolution in the mixed liquid gas which accumulated within the 2 nd  mixing tub. 
         [0024]    According to the eighth embodiment, because the gas which is supplied from the gas supply section is carbon dioxide, it becomes possible to promote vascular movement within the tub occupant&#39;s body. 
         [0025]    For purposes of summarizing the invention and the advantages achieved over the related art, certain objects and advantages of the invention are described in this disclosure. Of course, it is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. 
         [0026]    Further aspects, features and advantages of this invention will become apparent from the detailed description of the preferred embodiments which follow. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0027]    These and other features of this invention will now be described with reference to the drawings of preferred embodiments which are intended to illustrate and not to limit the invention. 
           [0028]      FIG. 1  is a perspective diagram of tub  3  which appropriately uses the mixing device for a tub  1  which is related to Embodiment 1 of this invention. 
           [0029]      FIG. 2  is a diagram which schematically shows the flow of the water and gas of the mixing device for a tub  1  which is related to Embodiment 1 of this invention. 
           [0030]      FIG. 3  is an explanatory diagram which illustrates the 1 st  mixing tub  10  which forms the mixing device for a tub  1  which is related to Embodiment 1 of this invention. 
           [0031]      FIG. 4  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 1 of this invention. 
           [0032]      FIG. 5  is a partial section view which illustrates from the side the supply pipe  220  which is provided to the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 1. 
           [0033]      FIG. 6  is an explanatory diagram which illustrates the periphery of the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 2 of this invention. 
           [0034]      FIG. 7  is an explanatory diagram which illustrates the periphery of the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 3 of this invention. 
           [0035]      FIG. 8  is an explanatory diagram which illustrates the periphery of the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 4 of this invention. 
           [0036]      FIG. 9  is an explanatory diagram which illustrates the periphery of the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 5 of this invention. 
           [0037]      FIG. 10  is an explanatory diagram which illustrates the periphery of the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 6 of this invention. 
       
    
    
     EXPLANATION OF THE ELEMENTS 
       [0038]      1 —mixing device for a tub 
         [0039]      3 —tub 
         [0040]      10 —1 st  mixing tub 
         [0041]      11 —container 
         [0042]      12 —cover member 
         [0043]      12   a —flow-in hole 
         [0044]      12   b —flow-out hole 
         [0045]      13 —cylinder-shaped body 
         [0046]      13   a —lower end opening 
         [0047]      13   b —upper end opening 
         [0048]      20 —2 nd  mixing tub 
         [0049]      21 —open-close valve 
         [0050]      23 —backflow wall 
         [0051]      24 —circulating pump 
         [0052]      25 —flow-in path 
         [0053]      26 —flow-out path 
         [0054]      31 —supply path 
         [0055]      32 —recovery circulating path 
         [0056]      33 —flow path 
         [0057]      34 —intermediate supply path 
         [0058]      35 —flow path 
         [0059]      36 —discharge water path 
         [0060]      41 —water supply section 
         [0061]      42 —gas supply section 
         [0062]      43 —pump 
         [0063]      51 —open-close valve 
         [0064]      61 —open-close valve 
         [0065]      62 —open-close valve 
         [0066]      63 —switching valve 
         [0067]      220 —supply pipe 
         [0068]      230 —supply pipe 
         [0069]      240 —supply pipe 
         [0070]      221 —hole 
         [0071]      222 —opening 
         [0072]      301 —tub for limbs (arms) 
         [0073]      302 —tub for legs 
         [0074]      303 —column, post 
         [0075]      310 —long chair 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0076]    The present invention will be explained with reference to preferred embodiments and drawings. However, the preferred embodiments and drawings are not intended to limit the present invention. 
         [0077]    The present invention is described by referring to figures. Additionally, “the present invention” aims to mean “an embodiment of the present invention”, but “an embodiment of the present invention” does not aim to limit the present invention thereby. 
         [0078]    In the present disclosure where conditions and/or structures are not specified, the skilled artisan in the art can readily provide such conditions and/or structures, in view of the present disclosure, as a matter of routine experimentation. 
         [0079]    Hereafter there is an explanation of implementations of this invention, based on the included drawings. 
         [0080]      FIG. 1  is a perspective view which shows the tub  3  which is appropriate to use for the mixing device for a tub which is related to embodiment 1 of this invention. 
         [0081]    This tub  3  is comprised of the tub for arms  301  and the tub for legs  302 , with both tubs connected in the up and down direction by the columns  303 . The user is seated at a long chair  310  which is arranged in front of the tub  3 , and by immersing his arms and legs in the tub for arms  301  and the tub for legs  302 , it is possible to locally promote blood circulation within the body. 
         [0082]      FIG. 2  is a diagram which shows schematically the flow of gas and liquid of the mixing device  1  which is necessary for Embodiment 1 of this invention. 
         [0083]    The mixed liquid which has been mixed with gas by this mixing device for a tub is supplied to the tub  3  by means of the supply path  31 . The mixed liquid which flows out from the tub  3  circulates within the mixing device for a tub through the use of a pump  43  which is provided by the mixing device for a tub  1  through the flow path  35 , and once again is supplied to the tub  3 . 
         [0084]    This mixing device for a tub provides a pair of 1 st  mixing tubs  10 , a 2 nd  mixing tub  20 , a supply path  31  to the tub  3 , a recovery circulating path  32  which reaches as far as the 1 st  mixing tub from the tub  3 , a water supply section  41  which supplies water to the recovery circulating path  32 , a gas supply section  42  which supplies gas to the recovery circulating path  32 , and a pump  43  for circulating the mixed liquid within the mixing device for a tub  1 . 
         [0085]    The water supply section  41  provides a water supply mechanism for supplying water to the recovery circulation section  32 . An open-close valve  61  is provided in the connection pipe between the water supply section  41  and the recovery circulating path  32 . It is possible to adjust the water supply amount. With this ability to regulate the amount of water, and from considerations of the amount of water which circulates within the mixing device for a tub and accumulates in the tub  3 , it becomes possible to appropriately supply the necessary amount of water. 
         [0086]    The gas supply section  42  provides a mechanism which supplies gas for enhancing the bath, such as carbon dioxide, to the recovery circulating path  32 . An open-close valve  62  is provided within the connection pipe between the gas supply section  42  and the recovery circulating path  32 , and with this valve, it becomes possible to adjust the amount of gas which is supplied to the water which circulates within the mixing device for a tub  1  and accumulates in the tub  3 . In addition, by connecting the gas supply section  42  to the recovery circulating path  32 , the gas separates from the mixed liquid, which was supplied to the tub  3 , whose top part is open to the atmosphere. The gas dissolution of the mixed liquid can be reduced, but it becomes possible to replenish with new gas as far as the 1 st  mixing tub  10  by means of the recovery circulating path  32 . 
         [0087]    A switching valve  63  is provided between the flow path  35  from the tub  3  and the recovery circulating path  32  for switching the flow path of the mixed liquid which flows out from the tub  3 . With this valve, it becomes possible to directly discharge water from the tub  3 . 
         [0088]    The 1 st  mixing tub  10  and the 2 nd  mixing tub  20  are serially connected to the flow path from the recovery circulating path  32  to the tub  3 . 
         [0089]      FIG. 3  is an explanatory diagram illustrating the 1 st  mixing tub  10  which forms this mixing device for the tub  1 . 
         [0090]    The 1 st  mixing tub  10  provides a cylinder-shaped container which has an opening on top, cover member  12  for closing the opening of the container  11 , and a cylinder-shaped body  13  which is established within the container  11 . The cover member  12  is formed from the flow-in hole  12   a  which is inserted into the container  11 , connecting to the circulating supply path  32 , and from the flow-out hole  12   b  which is inserted into the container  11 , connecting to the flow path  33 . The cylinder-shaped body  13  has a lower end opening  13   a , which is disposed close to the base of the container  11 , and an upper end opening  13   b , both of which are connected to the flow path  33  by means of the flow-out hole  12   b  of the cover member  12 . 
         [0091]    Because of this arrangement, the mixed liquid which is supplied from the recovery circulating path  32  becomes discharged to the flow path  33  after reaching the base of the container  11 . By this discharge and from the difference in specific gravity between the liquid and gas, a backflow is generated within the container  11  by liquid flow which is supplied from the gas flow, which rises, and the recovery circulating path  32 . It becomes possible to dissolve to an appropriate degree the gas in the liquid. 
         [0092]    The flow path  33  is further connected to the 1 st  mixing tub, and the mixed liquid passes through the same process previously described and flows into the intermediate circulating path  34 . 
         [0093]      FIG. 4  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which forms this mixing device for a tub  1 .  FIG. 5  is a partial sectional diagram which illustrates, from a side surface the supply pipe  220  which is provided to this 2 nd  mixing tub  20 . 
         [0094]    This 2 nd  mixing tub  20  has an L-shape and provides a supply pipe  220 , as shown in  FIG. 5 . The supply pipe  220  is connected to the intermediate supply path  34  from the 1 st  mixing tub  10 . The mixed liquid accumulates in the 2 nd  mixing tub  20  by means of this supply pipe  220 . 
         [0095]    Multiple holes  221  have been drilled in the supply pipe  220 . Through a connection of this supply pipe  220  to the intermediate supply path  34 , the mixed liquid is supplied to the 2 nd  mixing tub  20  by passing through these multiple holes  221  from the intermediate supply path  34 . Because of this supply, the mixed liquid is released to the shower-shape object within the mixed liquid which has accumulated in the 2 nd  mixing tub  20 . It becomes possible to enhance the dissolution efficiency of the gas. Because the supply pipe  220  is immersed in mixed liquid at this time, a backflow is generated within the mixed liquid which had accumulated in the 2 nd  mixing tub  20  through the flowing-out of the liquid from the multiple holes  221 . Because of this backflow, it becomes possible to sufficiently dissolve gas in the mixed liquid within the 2 nd  mixing tub  20 . 
         [0096]    In addition, the 2 nd  mixing tub  20  provides an open-close valve  21  for air venting within the 2 nd  mixing tub  20 . The open-close valve  21  is formed to release when supplying the mixed liquid to the tub  3  from the 2 nd  mixing tub  20 , and when supplying the mixed liquid to the tub  3  from the 2 nd  mixing tub  20 , and for preventing contact of the mixed liquid and outside air within the 2 nd  mixing tub  20 , it is desirable to form the open-close valve so that there is no release. For example, it is good to release the open-close valve  21  only when discharging liquid which is accumulating within the 2 nd  mixing tub  20  or the tub  3 . 
         [0097]    Moreover, there is provided an open-close valve  51  in the intermediate supply path  34  from the 1 st  mixing tub  10  to the 2 nd  mixing tub  20 . It becomes possible, by providing an open-close valve  51  to the intermediate supply path  34 , to adjust the force of the mixed liquid within the intermediate supply path  34 . While increasing pressure of the mixed liquid within the intermediate supply path by locally narrowing the liquid path of the intermediate supply path  34  and by supplying to the 2 nd  mixing tub  20 , it is possible to promote dissolution of the gas in the mixed liquid, which is not yet saturated with gas. 
         [0098]    In addition, the open-close valve  51  may be formed to be included in, in addition to the intermediate supply path  34 , the flow path  33 . 
         [0099]    Mixing the gas and liquid, using this mixing device for a tub  1 , is done first by releasing the open-close valve  61  and the open-close valve  62 , supplying water to the recovery circulating path  32  by the water supply section  41 , and mixing the gas from the gas supply section in this water. 
         [0100]    After the water and the gas, which was supplied to the recovery circulating path  32 , passes through the mixing process by the pair of 1 st  mixing tub  10 , the gas accumulates in the 2 nd  mixing tub  20 , further mixing and dissolving. 
         [0101]    The mixed liquid which has accumulated in the 2 nd  mixing tub  20  is supplied to the tub  3 . If the flow path of the mixed liquid which has flowed-out from the tub  3  is connected to the recovery circulating path  32  by the switching valve  63 , circulation occurs within the mixing device for a tub  1 , and if connected to the discharge water path  36  by the switching valve  63 , the mixed liquid discharges water to the outside of the mixing device for a tub  1 . 
         [0102]    Moreover, in order to supply continuously to the tub  3  mixed liquid which normally mixes gas, it is desirable to have the connection site towards the recovery circulating path  32  of the gas supply section  42 , assuming the site is downstream from the water supply section  41 , and be of a construction such that the gas is mixed before the supplied water arrives at the 1 st  mixing tub  10 . However, a construction such that the water supply section  41  is connected to the tub  3  is permissible. 
         [0103]    As stated above, with this embodiment, by providing multiple mixing tubs which have identical mixing mechanisms or by providing furthermore assembly of multiple mixing tubs which have different mixing mechanisms, it is possible to supply to the tub  3  mixed liquids in which gases sufficiently dissolve in water. 
         [0104]    Moreover, the recovery circulating tub  32  has a construction, in addition to that of the 1 st  mixing tub  10 , which may connect a mixed liquid filtering device and the like. 
         [0105]      FIG. 6  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which forms a mixing device for a tub which is related to Embodiment 2. 
         [0106]    This 2 nd  mixing tub  20  differs from the 2 nd  mixing tub  20  which formed the mixing device for a tub  1  which is related to Embodiment 1 by having a backflow wall  23  in its interior, providing a re-circulating mixing mechanism which circulates mixed liquid which has accumulated within the 2 nd  mixing tub  20 . That is, the re-circulating mixing mechanism, by using the circulating pump  24 , has mixed liquid which flows-out to the circulating pump  24  from the 2 nd  mixing tub  20  by means of the flow-out path  26 , and by means of the supply pipe  220 , which is connected to the flow-in path  25  towards the 2 nd  mixing tub from the circulating pump  24 , has a construction which re-supplies within the mixing tub  20 . From this kind of structure, it becomes possible to further enhance the dissolution of the gas with the mixed liquid. 
         [0107]    In addition, the geometry of this 2 nd  mixing tub  20  has changed so that one side of its side wall has become a doglegged shape. From this shape change, there results the formation of a backflow wall at a diagonal position with the flow inlet of the mixed liquid from the intermediate supply path  34  within the 2 nd  mixing tub  20 . The water flow of the mixed liquid which has flowed in perpendicularly from the flow inlet towards the 2 nd  mixing tub  20  changes the direction of this flow by collision with the backflow wall  23 , and there occurs backflow for the accumulated mixed liquid within the 2 nd  mixing tub  20 . From this backflow, it becomes possible to further mix the gas into the mixed liquid. 
         [0108]      FIG. 7  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which formed the mixing device for a tub  1  which is related to Embodiment 3. 
         [0109]    This 2 nd  mixing tub  20  differs from the 2 nd  mixing tub which formed the mixing device for a tub  1  which is related to Embodiment 2. The holes  221  are not formed on the side peripheral surface of the supply pipe  230  which is provided in the interior of the mixing tub. There is supply of mixed liquid to the 2 nd  mixing tub  20  for this 2 nd  mixing tub  20  by the opening  222  at the upper end of the supply pipe  230 . This 2 nd  mixing tub  20  forms multiple holes at the opening  222 , and because there results a release of the mixed liquid in a spraying water condition by means of the multiple holes of the opening  222  within the tub, it is possible to enhance the dissolution in the mixed liquid. Moreover, the opening of the supply pipe  230  may be shaped like a nozzle. 
         [0110]      FIG. 8  is an explanatory diagram which illustrates the 2 nd  mixing tub which forms a mixing device for a tub  1  which is related to Embodiment 4. 
         [0111]    This 2 nd  mixing tub  20  differs from the 2 nd  mixing tub  2  which forms the mixing device for a tub  1  which is related to Embodiment 2, with no backflow wall  23  in the tub&#39;s interior. 
         [0112]    In addition, this 2 nd  mixing tub  20 , which is different from the 2 nd  mixing tub which formed the mixing device for a tub related to Embodiment 2, provides a water level sensor  44  within the mixing tub. Furthermore, the supply pipe  240 , which is disposed to the interior, is different from the supply pipe  220 , which is disposed within the 2 nd  mixing tub for Embodiment 2, at points which form the holes  221  at the part which protrudes upward from the water&#39;s surface of the mixed liquid of the 2 nd  mixing tub  20 , which is controlled by the water level sensor. 
         [0113]    The water level signal which is sensed by the water level sensor  44  is transmitted to the control section (not illustrated). With the water level signal, which is transmitted to the control section, being transmitted to the open-close valve  61  and the open-close valve  62  which convert to a signal which adjusts the degree of opening of the open-close valve  61  and the open-close valve  62  which adjust the supply amount from the water supply section  41  and the gas supply section  42 , there is adjustment of the water level within the 2 nd  mixing tub  20  so that there results a specified level for the water level sensor. 
         [0114]    Moreover, when the water level within the 2 nd  mixing tub  20  exceeds the specified level of the water level sensor, an alarm signal is generated, and in response to this alarm, the operator may adjust the degree of opening by hand of the open-close valve  61  and the open-close valve  62 . 
         [0115]    Because the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to this Embodiment 4 establishes a supply pipe which partially forms holes which protrude upward from the water surface of the mixed liquid of the 2 nd  mixing tub  20  which is controlled by the water level sensor  44 , there results supply to a shower-shaped object of the mixed liquid within the 2 nd  mixing tub  20  by means of the holes  221  above the water surface of the mixed liquid, thereby making it possible to further dissolve within the mixed liquid gas which accumulates within the 2 nd  mixing tub. 
         [0116]      FIG. 9  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 5. 
         [0117]    This 2 nd  mixing tub  20  differs from the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 4 at points where its vertical cross-section is rectangular. 
         [0118]    Moreover, the supply pipe  240  which is established in the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiments 4 and 5 may be the supply pipe  220  which is established in the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 2 or may be the supply pipe  230  which is established in the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 3. With any of the supply pipes, by spraying the mixed liquid on top of the liquid surface of the mixed liquid, it is possible to further dissolve in the mixed liquid gas which accumulates within the 2 nd  mixing tub  20 . 
         [0119]      FIG. 10  is an explanatory diagram which illustrates the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 6. 
         [0120]    This 2 nd  mixing tub  20  differs from the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 5, and does not provide a re-circulating mixing mechanism. In the same way as with the supply pipe  220  which was provided to the 2 nd  mixing tub  20  which forms the mixing device for a tub  1  which is related to Embodiment 1, the mixed liquid passes through the multiple holes  221  of the supply pipe  220  from the intermediate supply path  34 , and being supplied to a shower shaped object, the mixed liquid forms on top of the water surface of the mixed liquid which accumulated in the 2 nd  mixing tub  20 . 
         [0121]    In this embodiment, by the above described description, it becomes possible to incorporate mixed liquid which is supplied to the 2 nd  mixing tub  20  from the intermediate supply path  34  and further incorporate gas which has been accumulating within the 2 nd  mixing tub  20  within the mixed liquid. 
         [0122]    Moreover, in the above described embodiments, for the supply path  31  directed towards the tub  3 , a recovery means may be established which recovers by separating from the liquid the gas which has separated from the liquid. It is also permissible to establish a new pipe path so as to lead, once again to the spray outside of the pump  43  of the recovery circulating path  32 , gas that has been recovered by this recovery means. 
         [0123]    In addition, the 2 nd  mixing tub  20  which forms the mixing device for a tub  1 , with this new pipe path, may be formed so as to connect with the flow-in path  25  to the 2 nd  mixing tub  20  from the recovery circulating path  32  as in Embodiments 2-5 which are shown in  FIGS. 6-9  which provide the re-circulating mixing mechanism. 
         [0124]    The present application claims priority to Japanese Patent Application No. 2006-60967, filed Mar. 7, 2006, and No. 2006-275039, filed Oct. 6, 2006, the disclosure of which is incorporated herein by reference in their entirety. 
         [0125]    It will be understood by those of skill in the art that numerous and various modifications can be made without departing from the spirit of the present invention. Therefore, it should be clearly understood that the forms of the present invention are illustrative only and are not intended to limit the scope of the present invention.