Patent Publication Number: US-11045374-B2

Title: Incubator

Description:
RELATED APPLICATIONS 
     This application is a 371 application of PCT/JP2018/002654 having an international filing date of Jan. 29, 2018, which claims priority to JP2017-014034 filed Jan. 30, 2017, the entire content of each of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an incubator capable of incubating a baby inside a baby accommodation chamber which can be shielded from external air. 
     2. Description of the Related Art 
     In a closed-type incubator for incubating a baby in an environment shielded from external air includes a humidifier which adjusts humidity of air to be supplied to a baby accommodation chamber for accommodating the baby in order to always maintain substantially constant humidity of the baby accommodation chamber. For such a humidifier, in order to facilitate water supply to the humidifier, a configuration in which the humidifier is attachable to and detachable from an incubator main body has been proposed. 
     For example, Patent Document 1 or Patent Document 2 discloses an incubator including a detachable humidifier. The incubators include a water storage tank which is attachable to and detachable from a humidifying tank (water tank) of the humidifier (heating type humidifier). Water is supplied into the humidifying tank from an inside of the water storage tank. Steam is generated by heating the water in a heating unit disposed inside the humidifying tank so as to humidify the air. In addition, the humidifying tank has a water level sensor which detects a water level of the water supplied into the humidifying tank so that the water level inside the humidifying tank can be controlled up to a predetermined depth. In addition, according to the incubator including the humidifier, as disclosed in Patent Document 1, the steam is continuously generated in the humidifier, when no more water remains inside the water storage tank and the water level inside the humidifying tank drops below a top portion of the water level sensor, an alarm is issued. Therefore, an operator detaches the humidifier from the incubator main body in response to the alarm. The operator can continuously humidify the air by supplying the water to the water storage tank, or can clean the humidifying tank of the humidifier. 
     3. Prior Art Documents 
     Patent Documents 
     
         
         Patent Document 1: Japanese Unexamined Patent Application, First publication No. 2001-70367 
         Patent Document 2: Japanese Patent (Granted) Publication No. 5956257 
       
    
     SUMMARY OF THE INVENTION 
     Technical Problem to be Solved by Invention 
     In this way, as the humidifier included in the incubator, a configuration including a detachable water storage tank is adopted. However, according to the humidifier including the water storage tank, if the humidifier is detached from the incubator main body and the water storage tank is not further detached from the humidifying tank, the water cannot be supplied to the water storage tank. Consequently, it takes time and effort to supply the water, and the work becomes complicated. In addition, when the water is supplied to the water storage tank, the humidifier is detached from the incubator main body. Accordingly, the humidifier temporarily stops humidifying the air, thereby causing a possibility that the humidity of the baby accommodation chamber may fluctuate. In addition, the operator cannot recognize the amount of the water stored inside the humidifying tank until the alarm is issued by the water level sensor. Therefore, in a case where a response of the operator is delayed, there is a possibility that the humidity of the baby accommodation chamber may fluctuate. Furthermore, each time the water is supplied to the water storage tank, a plurality of the operators touch the humidifying tank. Consequently, it is difficult to ensure satisfactory hygienic conditions. 
     In addition, when the humidifier is attached to and detached from the incubator main body, operation noise or shock may occur, thereby causing stress on the baby accommodated in the baby accommodation chamber. In addition, when the humidifier is attached thereto or detached therefrom, there is a possibility that the water remaining inside the humidifying tank may spill around the incubator. In addition, in the humidifying tank, a cap of a water supply tank is likely to become hot due to heated water. Therefore, when the water storage tank needs to be supplied with the water, it is difficult to immediately supply the water. 
     The present invention is made in view of the above-described circumstances, and aims to provide an incubator which can continuously humidify air and can stably supply hygienic air to a baby accommodation chamber. 
     Solution to Problem 
     According to the present invention, there is provided an incubator including an incubator main body, a baby accommodation chamber disposed in the incubator main body and capable of being shielded from external air, and a humidifier disposed in the incubator main body so as to generate steam for supplying humidified air into the baby accommodation chamber. The humidifier has a connection portion to which a water supply hose is connectable so as to supply water for generating the steam from a water supply container located outside the incubator main body. The humidifier includes a humidifying tank which stores the water for generating the steam, a water supply port portion which supplies the water into the humidifying tank in communication with the connection portion, and a float valve which opens and closes the water supply port portion by moving upward and downward in response to a water level of the water stored inside the humidifying tank. The float valve includes a guide shaft portion and an arm portion. The guide shaft portion is disposed substantially vertically in an axial direction, and an upper end portion of the guide shaft portion has a valve body capable of coming into contact with the water supply port portion. The arm portion is disposed to be rotatable around a base end portion by using the base end portion as a fulcrum, a tip portion of the arm portion has a float movable upward and downward by using buoyancy in response to the water level of the water stored inside the humidifying tank, and the arm portion is rotatably connected to a lower end portion of the guide shaft portion by a joint portion disposed at a position closer to the base end portion than the float. The guide shaft portion is disposed so as to be movable upward and downward in conjunction with upward and downward movement of the joint portion. When the float moves upward, the valve body comes into contact with the water supply port portion so as to close the water supply port portion. When the float moves downward, the valve body is separated from the water supply port portion so as to open the water supply port portion. 
     In the incubator according to the present invention, the water can be supplied to the humidifier from the water supply container located outside the incubator main body. Accordingly, an operator does not need to detach the humidifier from the incubator main body, and can supply the water to the water supply container or can easily replace the water supply container with another water supply container having the water stored therein. Therefore, the water can be continuously supplied to the humidifier, and humidified air can be stably and continuously supplied to the baby accommodation chamber. 
     In addition, when the operator replaces the water supply container, the operator does not need to detach the humidifier from the incubator main body. Accordingly, the operator does not touch the humidifying tank of the humidifier. Therefore, satisfactory hygienic conditions of the humidifying tank can be ensured, and hygienic air can be stably supplied to the baby accommodation chamber. Furthermore, unless the humidifier is detached from the incubator main body, there is no operation noise or shock caused by the attachment and detachment of the humidifier. Accordingly, it is possible to alleviate stress on a baby accommodated in the baby accommodation chamber. The humidifier may be detached from the incubator main body only when cleaning work is carried out. The humidifying tank can be easily and reliably cleaned and disinfected by detaching the humidifier from the incubator main body. 
     In addition, as the water supply container, for example, the operator uses a container formed so that a remaining amount of the internally stored water can be visually confirmed such as a container formed of a transparent member. Accordingly, the operator can easily confirm the remaining amount of the water stored inside the water supply container. In this case, the operator can recognize in advance a timing to replace the water supply container without waiting for an alarm. The operator can supply the water to the water supply container, and can prepare for replacing the water supply container with another water supply container having the water stored therein. Since the operator can prepare the replacement in this way, the water can be smoothly and quickly supplied to the water supply container. Without stopping the water supply to the humidifier, the operator easily and continuously supplies the humidified air to the baby accommodation chamber. 
     In addition, in the incubator according to the present invention, the humidifier has the float valve, and the water is automatically supplied into the humidifying tank by opening and closing the water supply port portion in accordance with the upward and downward movement of the float valve. Accordingly, the water level inside the humidifying tank can be kept constant. Therefore, the water can be continuously supplied from the water supply container to the humidifier, and the humidified air can be stably and continuously supplied to the baby accommodation chamber. 
     In addition, the arm portion of the float valve has the float (power point) in which buoyancy is applied to the tip portion by using the base end portion as a fulcrum. The joint portion (point of action) to which the guide shaft portion is connected is disposed at the position closer to the base end portion (fulcrum) than the float (power point). In this way, the arm portion is disposed so that a distance from the base end portion (fulcrum) to the float (power point) that is farther than a distance from the base end portion (fulcrum) to the joint portion (point of action). In this manner, when a weak force (buoyancy) is applied to the float (power point), a force stronger than a force applied to the float (power point) can be applied to the joint portion (point of action). Therefore, in the humidifier, the water supply port portion can be reliably closed so as to stop the water supply by using the float valve, and the water can be prevented from being excessively supplied into the humidifying tank. Therefore, in the humidifier, the water supply port portion can be reliably closed and opened in conjunction with the upward movement and the downward movement of the float. 
     The water supply container is located at a position higher than the water supply port portion of the humidifier. In this manner, the water can be supplied into the humidifying tank by utilizing gravity generated due to the height (gravity supply method). In this case, the water can be supplied to the humidifier by adopting a simple configuration without providing means for forcibly supplying the water, such as a water pump. 
     As a preferred embodiment of the incubator according to the present invention, the arm portion may have a bilaterally symmetrical shape, and a pair of the base end portions may be disposed in a rightward-leftward direction. 
     The arm portion is caused to have the bilaterally symmetrical shape, and the pair of base end portions is disposed in the rightward-leftward direction. In this manner, it is possible to suppress inclination of the float when the buoyancy is applied to the float (power point). Therefore, the arm portion can be stably rotated around the base end portion (fulcrum). The water supply and the water supply stop can be reliably switched by the float valve. 
     In the incubator according to the present invention, the humidifier may include a water level sensor which detects the water level of the water stored inside the humidifying tank. 
     In a case where the water is not properly supplied to the humidifier, humidification efficiency may become poor, thereby causing a possibility that the air may not be sufficiently humidified. In addition, there is a possibility that so-called no-water heating phenomenon may appear where the humidifying tank is heated in a state where no water exists inside the humidifying tank. Therefore, the water level sensor which detects the water level of the water stored inside the humidifying tank is disposed therein. In this manner, when the water level drops below a predetermined water level, a warning is issued so as to inform the operator of an abnormal water level inside the humidifying tank. Accordingly, the operator can take various safety measures by reliably supplying the water into the humidifying tank or by forcibly stopping the heating performed by the humidifier. In this manner, the no-water heating can be prevented, and the humidified air can be stably supplied to the baby accommodation chamber. 
     As a preferred embodiment of the incubator according to the present invention, the water level sensors may be respectively attached to two positions having mutually different depths of the humidifying tank. 
     The water level can be checked in two stages by using the water level sensors respectively attached to the two positions having the mutually different depths of the humidifying tank. Therefore, the operator can take various safety measures in two stages. 
     As a preferred embodiment of the incubator according to the present invention, a central portion of the float in the rightward-leftward direction may have a recessed portion formed to be recessed in a forward-rearward direction orthogonal to the rightward-leftward direction. The water level sensor may be arranged inside the recessed portion. 
     The recessed portions are respectively formed in front of and behind the float, and the two water level sensors are respectively located inside the recessed portions. In this manner, the plurality of water level sensors can be arranged even in a limited space inside the humidifying tank. 
     As a preferred embodiment of the incubator according to the present invention, a bottom surface portion of the humidifying tank may be formed so that the depth of one side portion in the forward-rearward direction is shallow and the depth of the other side portion is deep, and an inclined surface is formed between the one side portion and the other side portion. The water level sensors may be respectively attached to two locations of the inclined surface. 
     The water level sensors are respectively attached to the two locations of the inclined surface formed on the bottom surface portion of the humidifying tank. In this manner, the respective water level sensors can be easily arranged at positions having the mutually different depths of the humidifying tank. 
     Advantageous Effects of Invention 
     According to the present invention, air can be continuously humidified, and hygienic air can be stably supplied to a baby accommodation chamber. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an external perspective view of an incubator, which illustrates an embodiment according to the present invention. 
         FIG. 2  is a side view of the incubator illustrated in  FIG. 1 . 
         FIG. 3  is a front view of a main part of the incubator when viewed from a left side in  FIG. 2 . 
         FIG. 4  is a sectional view of a main part of the incubator, which is taken along line A-A in  FIG. 3 . 
         FIG. 5  is a perspective view illustrating the incubator in a state where a floor plate is exposed by removing a bed base located in a lower portion of a baby accommodation chamber. 
         FIG. 6  is a perspective view illustrating the incubator in a state where a harmonizing tank and an air conditioner are exposed by removing the floor plate of the baby accommodation chamber. 
         FIG. 7  is a sectional view of a main part of the incubator, which is taken along line B-B in  FIG. 3 . 
         FIG. 8  is a plan view illustrating a humidifier to be installed in the air conditioner of the incubator illustrated in  FIG. 1 . 
         FIG. 9  is an exploded perspective view of a lid portion of the humidifier illustrated in  FIG. 8 . 
         FIG. 10  is a sectional view taken along line C-C of the humidifier illustrated in  FIG. 8 . 
         FIG. 11  is a sectional view of a main part of the incubator for describing the humidifier to be attached to and detached from a base. 
         FIG. 12  is a sectional view of a main part of the incubator for describing an operation of a float valve. The part (a) of  FIG. 12  illustrates a state where a water supply port portion is closed, and the part (b) of  FIG. 12  illustrates a state where the water supply port portion is open. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, an incubator according to an embodiment of the present invention will be described with reference to the drawings. 
     As totally illustrated in  FIG. 1 , an incubator  101  according to the present embodiment includes a pedestal  12  movable by using a caster  11 , a support pillar  13  vertically erected on the pedestal  12 , a frame  14  disposed in an upper end of the support pillar  13 , a base  15  installed on the frame  14 , a hood  17  disposed on the base  15  and surrounding a baby accommodation chamber  16 , two guide pillars  18  and  19  vertically disposed at side positions of the hood  17  in one end portion of the frame  14 , a canopy (ceiling hood)  20  attached to an upper end of the guide pillar  18  and configuring a ceiling of the hood  17 , and an air heater  21  attached to an upper end of the guide pillar  19 . In the incubator  101  according to the present embodiment, each portion of the base  15  and the hood  17  which are arrayed on the frame  14  corresponds to an incubator main body according to the present invention.  FIG. 3  is a front view of a main part of the incubator  101 , and  FIG. 4  is a sectional view of the main part of the incubator  101 . 
     The hood  17  is configured to have a substantially rectangular shape by using a floor plate  23  on which a bed base  22  is installed to lay a baby thereon, respective treatment doors  24  arranged on a right side, a left side, a foot side, and a head side of the baby, and a canopy  20  which closes an upper portion of the baby accommodation chamber  16  surrounded by the treatment doors  24 . Sealing members are respectively arranged among the floor plate  23  forming the hood  17 , the respective treatment doors  24 , and the canopy  20 . In this way, it is possible to form the baby accommodation chamber  16  shielded from external air. In addition, substantially all of the respective treatment doors  24  and the canopy  20  are formed of a transparent resin, thereby enabling the baby inside the baby accommodation chamber  16  to be visually confirmed from the outside. 
       FIGS. 1 to 4  illustrate the incubator  101  in a state where the hood  17  is closed by lowering the canopy  20 . In the incubator  101 , the upper portion of the baby accommodation chamber  16  can be opened by raising the canopy  20 , or the respective treatment doors except the foot side can be opened. In this case, the baby accommodation chamber  16  can be heated by using the air heater  21 . In addition, in a state of a closed-type incubator in which the hood  17  is closed, an operator inserts a hand into the baby accommodation chamber  16  through a maintenance window  25  disposed in the respective treatment doors  24 . In this manner, the operator can treat the baby while the respective treatment doors  24  remain closed. 
     As illustrated in the sectional view of the base  15  in  FIG. 7 , a harmonizing tank  26  communicating with the baby accommodation chamber  16  is provided in a lower portion of the baby accommodation chamber  16 , that is, inside the base  15 . An air conditioner  27  is provided so that air whose temperature and humidity are harmonized through the harmonizing tank  26  is circulated in the baby accommodation chamber  16 . The air conditioner  27  includes a fan  28  which moves the air in the harmonizing tank  26 , a heater  29  which heats the air in the harmonizing tank  26 , and a humidifier  40  disposed to be attachable to and detachable from a harmonizing tank bottom plate (harmonizing tank configuration member)  30  configuring the harmonizing tank  26  and supplying the steam to the air in the harmonizing tank  26 . The air whose temperature and humidity are harmonized can be circulated for the baby accommodation chamber  16 . 
     The base  15  includes a base door  31  which is opened and closed when the humidifier  40  is detached from the harmonizing tank bottom plate  30 . As illustrated in  FIG. 11 , the base door  31  is closed, thereby allowing the humidifier  40  to be accommodated inside the base  15 . In addition, in the incubator  101 , as illustrated in  FIGS. 1 and 2 , a water supply unit  70  for supplying the water to the humidifier  40  is attached to an outer portion of the base  15  which accommodates the humidifier  40 . 
       FIG. 5  illustrates a state where the floor plate  23  is exposed by detaching the bed base  22  and the respective treatment doors  24 . In the incubator  101 , the baby accommodation chamber  16  and the air conditioner  27  are isolated from each other by the floor plate  23 . The harmonizing tank  26  is formed below the floor plate  23 . The air is fetched from the baby accommodation chamber  16  to the harmonizing tank  26  through an opening portion  23 A disposed close to a rear side (right side in  FIG. 2 ) on the floor plate  23 . The air whose temperature and humidity are harmonized in the harmonizing tank  26  is supplied from the harmonizing tank  26  to the baby accommodation chamber  16  through an opening portion  23 B disposed in both side portions of the floor plate  23 . 
       FIG. 6  illustrates a state where the floor plate  23  is further detached therefrom. The harmonizing tank bottom plate  30  located in a lower portion of the floor plate  23  has a first recessed portion  30 A disposed so as to form a space with a lower surface of the floor plate  23 , a substantially cylindrical second recessed portion  30 B further recessed from a bottom surface of the first recessed portion  30 A so as to accommodate the fan  28 , and a substantially rectangular third recessed portion  30 C formed continuously with the second recessed portion  30 B along a longitudinal direction (forward-rearward direction) of the incubator  101  so as to accommodate the heater  29 . In addition, an external air inlet  30 D is disposed in the vicinity of the second recessed portion  30 B of the harmonizing tank bottom plate  30 . Furthermore, in front (downstream side) of the third recessed portion  30 C of the harmonizing tank bottom plate  30 , a steam introduction port  32  connected to the humidifier  40  is disposed by penetrating in a substantially upward-downward direction of the harmonizing tank bottom plate  30  extending in a substantially horizontal direction. 
     In the harmonizing tank  26  formed between the harmonizing tank bottom plate  30  and the floor plate  23 , the air inside the baby accommodation chamber  16  which is suctioned from the guide pillars  18  and  19  by the fan  28  and external air supplied from the external air inlet  30 D are introduced to the second recessed portion  30 B through the first recessed portion  30 A. Then, the air flows into the third recessed portion  30 C from the second recessed portion  30 B, and is heated by the heater  29 . Furthermore, the air is humidified by the steam supplied from the humidifier  40  through the steam introduction port  32 . Thereafter, the humidified air is supplied into the baby accommodation chamber  16  through the first recessed portion  30 A from between the floor plate  23  on a lateral side of the baby accommodation chamber  16  and the harmonizing tank bottom plate  30 . In  FIG. 7 , a flow of the air in the air conditioner  27  configured to include the harmonizing tank  26  formed by the floor plate  23  and the harmonizing tank bottom plate  30 , the heater  29 , and the humidifier  40  is indicated by an arrow. 
     The humidifier  40  of the air conditioner  27  is illustrated in  FIGS. 8 to 10 . The humidifier  40  includes a humidifying tank  41  which stores the water for generating the steam, and a lid portion  51  which covers an upper portion of the humidifying tank  41 . As illustrated in  FIG. 10 , the humidifying tank  41  has a recessed water storage  42  which is open upward. A bottom surface portion  420  of the water storage  42  is formed so that the depth of one side portion in the forward-rearward direction is shallow and the depth of the other side portion is deep. An inclined surface  421  is formed between the one side portion and the other side portion. Then, the water supplied into the humidifying tank  41  (water storage  42 ) can be collected in a deepest portion  422  of the other side portion formed to be deepest in the bottom surface portion  420  of the water storage  42 . Then, a steam tower  43  having a steam supply port  40   a  connected to the steam introduction port  32  formed in a downstream side end portion of the third recessed portion  30 C of the harmonizing tank bottom plate  30  is attached to the deepest portion  422  of the water storage  42 . A cartridge heater  44  is located inside the steam tower  43 . 
     In this humidifier  40 , if the water supplied from the water supply unit  70  into the humidifying tank  41  is heated by the cartridge heater  44  located inside the steam tower  43 , the generated steam is discharged from the steam supply port  40   a  of the steam tower  43 . 
     In addition, the water level sensor  45  for detecting the water level of the water stored inside the humidifying tank  41  is attached to the inclined surface  421  of the water storage  42  of the humidifying tank  41 , and checks the water level of the water stored inside the humidifying tank  41  and the amount of the water to be supplied to the cartridge heater  44 . In addition, the water level sensors  45  are respectively installed at two positions having the mutually different depths of the water storage  42 , and the water level is checked in two stages. As illustrated in  FIGS. 10 to 12 , the water level sensor  45  attached to the two positions of the inclined surface  421  are the same as each other. In this way, the water level sensors  45  are attached using the inclined surface  421 . Accordingly, the respective water level sensors  45  can be easily arranged at the positions having the mutually different depths of the water storage  42 . Then, when the water level of the humidifying tank  41  drops below a predetermined water level, in the incubator  101  is controlled so as to issue a warning of an abnormal water level inside the humidifying tank  41  or to stop power supply to the cartridge heater  44 . 
     The lid portion  51  is detachably disposed in the upper portion of the humidifying tank  41 , and the water storage  42  can be closed by attaching the lid portion  51  to the humidifying tank  41 , and the water storage  42  can be open by detaching the lid portion  51  from the humidifying tank  41 . In this case, as illustrated in  FIGS. 8 to 10 , the lid portion  51  includes a lid main body  52  which covers an upper opening of the water storage  42 . The lid main body  52  includes a cover member  53  and a float valve  61 . The cover member  53  has a connection portion  54  which can be connected to a water supply hose  72  for supplying the water for generating the steam from a water supply container  71  located outside the base  15 , and a water supply port portion  55  which supplies the water into the humidifying tank  41  in communication with the connection portion  54 . The float valve  61  is configured to move upward and downward in response to the water level stored inside the humidifying tank  41  so as to open and close the water supply port portion  55 . 
     As illustrated in  FIGS. 9 and 10 , the lid main body  52  has a guide hole portion  56  which guides the upward and downward movement of the float valve  61 , and a communication port portion  57  which is formed around the guide hole portion  56  so as to communicate with a lower surface side from an upper surface side of the lid main body  52 . Then, the cover member  53  is detachably disposed on an upper surface of the lid main body  52 . In a state where the cover member  53  is mounted on the lid main body  52  as illustrated in  FIG. 10 , the guide hole portion  56  and the communication port portion  57  are covered by the cover member  53 , thereby forming a small space portion  58  between the upper surface of the lid main body  52  and the cover member  53 . 
     The connection portion  54  is formed on the upper surface side of the cover member  53 . The water supply port portion  55  communicates with the connection portion  54 , and is disposed to be open on the lower surface side of the cover member  53 . In addition, as illustrated in  FIG. 10 , a packing  67  is interposed between the cover member  53  and the lid main body  52 . A portion between the cover member  53  and the lid main body  52  is sealed in an airtight manner by the packing  67 . Therefore, the water supplied from the water supply port portion  55  does not flow outward of the small space portion  58  from the portion between the cover member  53  and the lid main body  52 . The water is smoothly supplied into the humidifying tank  41  (water storage  42 ) through the communication port portion  57 . 
     As illustrated in  FIGS. 9 to 12 , the float valve  61  has a guide shaft portion  62  which engages with the guide hole portion  56  of the lid main body  52 , and an arm portion  63  having a float  65  formed in the tip portion. A lower end portion  621  of the guide shaft portion  62  and a joint portion  631  of the arm portion  63  are rotatably connected to each other. In this manner, both of these are integrally disposed therein. The guide shaft portion  62  is disposed so that an axial direction thereof is substantially vertical, and an intermediate portion thereof serves as an engagement shaft portion  622  which engages with the guide hole portion  56  of the lid main body  52 . 
     According to the present embodiment, as illustrated in  FIG. 9 , a cross-section of the engagement shaft portion  622  has a plus shape (+), and the engagement shaft portion  622  engages with the guide hole portion  56  only at four locations on the outer peripheral edge portion. Therefore, a relatively large gap is formed between the engagement shaft portion  622  and the guide hole portion  56 . The water supplied from the water supply port portion  55  is supplied not only to the communication port portion  57  but also into the water storage  42  through the guide hole portion  56 . 
     In addition, an upper end portion  623  of the guide shaft portion  62  is disposed so as to protrude from the upper surface of the lid main body  52 , and a valve body  64  which can come into contact with the water supply port portion  55  is attached to the upper end portion  623 . On the other hand, a lower end portion  621  of the guide shaft portion  62  is disposed so as to protrude from the lower surface of the lid main body  52 , and is rotatably connected to the joint portion  631  of the arm portion  63  as described above. 
     As described above, the arm portion  63  has the float  65  in the tip portion. The float  65  is hollow. As illustrated in the part (a) and the part (b) of  FIG. 12 , the float  65  moves upward and downward using the buoyancy in response to an increase or a decrease in the water level of water  95  stored inside the water storage  42 . In addition, a base end portion  632  of the arm portion  63  is rotatably supported by the lid main body  52 , and the arm portion  63  is disposed so as to be rotatable around the base end portion  632  by using the base end portion  632  as the fulcrum. Then, the arm portion  63  is rotatably connected to the lower end portion  621  of the guide shaft portion  62  via the joint portion (point of action)  631  disposed closer to the base end portion (fulcrum)  632  than the float (power point)  65  to which the buoyancy is applied. The guide shaft portion  62  is moved upward and downward in conjunction with the upward and downward movement of the joint portion  631 . 
     As described above, the joint portion  631  of the arm portion  63  is located at a position closer to the base end portion  632  than the float  65  disposed in the tip portion of the arm portion  63 . Accordingly, whereas the float  65  greatly moves upward and downward, the joint portion  631  less moves upward and downward as much as a movement amount which is smaller than a movement amount of the float  65 . In addition, the guide shaft portion  62  is connected to the joint portion  631  of the arm portion  63 . Accordingly, the guide shaft portion  62  moves upward and downward in conjunction with the upward and downward movement of the joint portion  631 , and less moves upward and downward than the float  65 . Then, the valve body  64  is attached to the upper end portion of the guide shaft portion  62 . Accordingly, the valve body  64  moves upward and downward in response to the upward and downward movement of the guide shaft portion  62 . 
     Therefore, as illustrated in the part (a) of  FIG. 12 , if the float  65  moves upward due to an increase in the water level of the water  95  stored inside the water storage  42 , the arm portion  63  is rotated upward around the base end portion  632 , and the guide shaft portion  62  is pressed upward via the joint portion  631 . Then, the guide shaft portion  62  moves upward with respect to the lid main body  52 , and the valve body  64  comes into contact with the water supply port portion  55 , thereby closing the water supply port portion  55 . On the other hand, as illustrated in the part (b) of  FIG. 12 , if the float  65  moves downward due to a decrease in the water level of the water  95  stored inside the water storage  42 , the arm portion  63  is rotated downward around the base end portion  632 , and the guide shaft portion  62  is pulled downward via the joint portion  631 . Then, the guide shaft portion  62  moves downward with respect to the lid main body  52 , and the valve body  64  is separated from the water supply port portion  55 , thereby opening the water supply port portion  55 . Therefore, as illustrated in the part (a) of  FIG. 12 , in a state where the valve body  64  is in contact with the water supply port portion  55 , the water supply from the water supply unit  70  is in a stopped state. As illustrated in the part (b) of  FIG. 12 , only in a state where the valve body  64  is separated from the water supply port portion  55 , the water is supplied from the water supply unit  70 . 
     The arm portion  63  has a bilaterally symmetrical shape as illustrated in  FIG. 9 , and is formed to have a constant width in the rightward-leftward direction. In addition, a pair of the base end portions  632  supported by the lid main body  52  of the arm portion  63  is disposed in the rightward-leftward direction, and is located at an interval therebetween. In addition, the float  65  disposed in the tip of the arm portion  63  is formed to be wider in the rightward-leftward direction. The central portion in the rightward-leftward direction has a recessed portion  651  recessed in the forward-rearward direction orthogonal to the rightward-leftward direction. Then, the water level sensors  45  are respectively arranged inside the recessed portion  651  formed in front of and behind the float  65 . In  FIG. 9 , positions at which the two water level sensors  45  are disposed are indicated by reference numerals P 1  and P 2 . In this way, the recessed portions  651  are respectively disposed in front of and behind the float  65 , and the water level sensors  45  are arranged inside the respective recessed portions  651 . In this manner, even in a limited space inside the humidifying tank  41 , a plurality of the water level sensors  45  can be arranged. 
     As illustrated in  FIGS. 1 and 2 , the water supply unit  70  for supplying the water to the humidifier  40  has a water supply container  71  for storing the water and a water supply hose  72  for connecting the water supply container  71  and the humidifier  40  to each other. The water supply container  71  is located outside the base  15 , and is formed so that the remaining amount of the water inside the water supply container  71  can be visually confirmed. For example, the water supply container  71  is formed of a transparent member so that an internal state can be observed from the outside. Specifically, the water supply container  71  is formed of polyethylene (PE) or polypropylene (PP). 
     In the water supply hose  72 , one end is connected to the water supply container  71 , and the other end is connected to the connection portion  54  disposed in the lid portion  51  of the humidifier  40 . Therefore, most of the water supply hose  72  is located outside the base  15 , but a portion (other end) is located inside the base  15 . A fixing support portion  68  is disposed in the lid portion  51 , and the other end portion side of the water supply hose  72  is fixed to the vicinity of the connection portion  54  by the fixing support portion  68 . In this manner, even if one end portion side of the water supply hose  72  located outside the base  15  may unexpectedly move, the water supply hose  72  is not easily removed from the lid portion  51 . Then, the water supply container  71  connected to the water supply hose  72  is located at a position higher than the water supply port portion  55  of the humidifier  40 . A gravity supply method utilizing gravity generated due to the height is used, thereby supplying the water from the water supply container  71  through the water supply hose  72  into the humidifying tank  41 . 
     As illustrated in  FIGS. 1 and 2 , the incubator  101  according to the present embodiment includes a support rod portion  81  having a hook portion  82  for suspending a medical container such as an infusion bag. The support rod portion  81  is vertically disposed similarly to the guide pillars  18  and  19 . Then, the water supply container  71  is suspended by the hook portion  82 . In this manner, the water supply container  71  is located at a position higher than the water supply port portion  55  of the humidifier  40 , where the inside of the water supply container  71  can be easily viewed by an operator. The water supply container  71  can be used by being attached to a separate device (such as a gator stand) other than the incubator  101 . 
     The humidifier  40  includes a lower container  48  having a substantially tray shape, and the humidifying tank  41  is attached onto the lower container  48 . The lower container  48  further includes a power supply connector  46  for supplying power to the cartridge heater  44 , and a handle  47  for reliably mounting the humidifier  40  on the base  15  (harmonizing tank bottom plate  30 ). As illustrated in  FIG. 7 , the handle  47  is attached so as to be rotatable around an attachment shaft  47   a , and is rotationally biased in a direction away from the lower container  48  by a torsion coil spring (not illustrated) attached to the attachment shaft  47   a.    
     As illustrated in  FIGS. 7 and 11 , if the base door  31  is closed in a state where the humidifier  40  is incorporated in the base  15 , the handle  47  is pressed and rotated by the base door  31  so that the humidifier  40  is biased toward the harmonizing tank bottom plate  30 . An upper portion of the base door  31  has a recessed groove portion  31   b  into which the water supply hose  72  can be inserted. In a state where the other end of the water supply hose  72  is connected to the connection portion  54  of the humidifier  40 , one end thereof can be pulled out via the base door  31 . 
     When the humidifier  40  is mounted, as illustrated in  FIG. 11 , the humidifier  40  inserted into the base  15  is pressed to the right in the horizontal direction until a tip of a connector pin  46   a  of the power supply connector  46  comes into contact with the plug  91  disposed inside the base  15 . As illustrated by an arrow in the drawing, the base door  31  is closed. Since the base door  31  is closed, the handle  47  is pressed against the base door  31  while being rotated around the attachment shaft  47   a . The humidifier  40  is moved in the horizontal direction, and is further pressed. 
     As the humidifier  40  is pressed, as illustrated in  FIG. 7 , the power supply connector  46  and the plug  91  are connected to each other, and the cartridge heater  44  can be heated. As illustrated in  FIG. 11 , an upper end surface  43   a  of the steam tower  43  is located below the steam supply path member  92 . In this manner, the steam supply path member  92  is pressed up, and further, the steam cap (cap member)  34  is pressed up and opened. In this manner, the steam supply port  40   a  of the humidifier  40  and the harmonizing tank  26  communicate with each other, and the steam can be supplied to the harmonizing tank  26 . 
     On the other hand, when the humidifier  40  is detached, as illustrated by a two-dot chain line in  FIG. 11 , the base door  31  is opened. In this manner, a claw  31   a  (refer to  FIGS. 7 and 11 ) of the base door  31  is rotated by engaging with a groove (not illustrated) of the humidifier  40 . The humidifier  40  is pressed by the claw  31   a , and is pulled out. The power supply connector  46  disengages from the plug  91 . In addition, if the base door  31  is opened, the handle  47  rotationally biased in a direction away from the lower container  48  is rotated, thereby forming a space for finger hooking. The humidifier  40  can be pulled out in the horizontal direction by gripping the handle  47 . 
     The steam tower  43  moves to the left in  FIG. 11  by pulling out the humidifier  40 . The steam supply path member  92  supported from below by the steam tower  43  is no longer supported from below, and moves downward. In this manner, a steam cap  34  pressed up by the steam supply path member  92  is rotated, the steam introduction port  32  is closed, and the harmonizing tank  26  maintains a state of being shielded from the external air. 
     Then, according to the incubator  101  configured in this way, if the water level drops after the water  95  stored inside the humidifying tank  41  (water storage  42 ) is consumed due to the steam generated by the humidifier  40  mounted on the base  15 , the float  65  moves downward due to the dropped water level of the water  95  stored inside the humidifying tank  41  as illustrated in the part (b) of  FIG. 12 . Then, the arm portion  63  is rotated downward around the base end portion  632  due to the downward movement of the float  65 . In addition, in conjunction with the joint portion  631  of the arm portion  63 , the guide shaft portion  62  moves downward with respect to the lid main body  52 . The valve body  64  is separated from the water supply port portion  55 , thereby opening the water supply port portion  55 . In this manner, the water is automatically supplied into the humidifying tank  41  from the water supply unit  70  (water supply container  71 ). 
     On the other hand, if the water is supplied into the humidifying tank  41  and the water level of the water  95  stored inside the humidifying tank  41  rises, as illustrated in the part (b) of  FIG. 12 , the float  65  moves upward due to the rising water level of the water  95  stored inside the humidifying tank  41 . Then, the arm portion  63  is rotated upward around the base end portion  632  due to the upward movement of the float  65 . In addition, in conjunction with the joint portion  631  of the arm portion  63 , the guide shaft portion  62  moves upward with respect to the lid main body  52 . The valve body  64  comes into contact with the water supply port portion  55 , thereby closing the water supply port portion  55 . In this manner, the water supply into the humidifying tank  41  is automatically stopped. 
     As described above, the joint portion (action point)  631  of the arm portion  63  is disposed at the position closer to the base end portion (fulcrum)  632  than the float (power point)  65 . Therefore, when a weak force (buoyancy) is applied to the float  65 , a force stronger than a force applied to the float  65  can be applied to the joint portion  631 . Then, the valve body  64  can be pressed against the water supply port portion  55  by using the force stronger than the buoyancy via the joint portion  631 . The water supply port portion  55  can be reliably closed, and the water supply can be stopped. Therefore, the water can be prevented from being excessively supplied into the humidifying tank  41 . 
     In addition, the arm portion  63  has the bilaterally symmetrical shape, and the pair of base end portions (fulcrum)  632  is disposed at an interval in the rightward-leftward direction. Accordingly, when the buoyancy is applied to the float  65 , it is possible to suppress the inclination of the float  65 . Therefore, the arm portion  63  can be stably rotated around the base end portion  632 , and the water supply and the water supply stop can be reliably switched by the float valve  61 . 
     Therefore, according to the incubator  101 , the water supply port portion  55  can be reliably closed and opened in conjunction with the upward movement and the downward movement of the float  65 . In addition, the water supply port portion  55  is opened and closed, thereby enabling the water to be automatically supplied into the humidifying tank  41 . Therefore, the water level inside the humidifying tank  41  can be kept constant. 
     In addition, the water stored inside the water supply container  71  is consumed by water supply into the humidifying tank  41 . However, the water supply container  71  is installed outside the base  15 . Accordingly, an operator can easily and visually confirm the remaining amount of the water stored in the water supply container  71 . Then, when the remaining amount of the water stored inside the water supply container  71  is small, the operator supplies the water to the water supply container  71 , or replaces the water supply container  71  with another water supply container having the water stored therein. In this manner, the operator can continuously supply the water to the humidifier  40 . Therefore, the operator can continuously supply the humidified air to the baby accommodation chamber  16 . 
     As described above, according to the incubator  101  of the present invention, the water can be supplied to the humidifier  40  from the water supply container  71  located outside the base  15  (incubator main body). Accordingly, without detaching the humidifier  40  from the base  15 , the operator can easily supply the water to the water supply container  71 , or can easily replace the water supply container  71  with another water supply container having the water stored therein. Therefore, the operator can continuously supply the water to the humidifier  40 , and can stably supply the humidified air to the baby accommodation chamber  16 . 
     In addition, the incubator  101  according to the present invention does not need to attach and detach the humidifier  40  to and from the base  15 , when the water supply container  71  is replaced. Accordingly, the operator does not touch the humidifying tank  41  of the humidifier  40 . Therefore, satisfactory hygienic conditions of the humidifying tank  41  can be ensured, and hygienic air can be stably supplied to the baby accommodation chamber  16 . Furthermore, unless the humidifier  40  is detached from the base  15 , there is no operation noise or shock caused by the attachment and detachment of the humidifier  40 . Accordingly, it is possible to alleviate stress on a baby accommodated in the baby accommodation chamber  16 . The humidifier  40  may be detached from the base  15  only when cleaning work is carried out. The humidifying tank  41  can be easily and reliably cleaned and disinfected by detaching the humidifier  40  from the base  15 . 
     In addition, as in the present embodiment, the operator uses the water supply container  71  formed so that the remaining amount of the internally stored water can be visually confirmed. Accordingly, the operator can easily confirm the remaining amount of the water stored inside the water supply container  71 . Therefore, the operator can recognize in advance a timing to replace the water supply container  71  without waiting for an alarm. The operator can supply the water to the water supply container  71 , and can prepare for replacing the water supply container  71  with another water supply container having the water stored therein. In addition, since the operator can prepare the replacement in this way, the water can be smoothly and quickly supplied to the water supply container  71 . Without stopping the water supply to the humidifier  40 , the operator easily and continuously supplies the humidified air to the baby accommodation chamber  16 . 
     In addition, according to the incubator  101  of the present embodiment, the water supply container  71  is located at the position higher than the water supply port portion  55  of the humidifier  40 . Accordingly, the water can be supplied into humidifying tank  41  by using the gravity supply method utilizing the gravity generated due to the height. Therefore, the water supply unit  70  can be simply configured without providing means for forcibly supplying the water such as a water pump. In addition, the float valve  61  is disposed in the humidifier  40 , and the water supply port portion  55  is opened and closed in response to the upward and downward movement of the float valve  61 . In this manner, the water can be automatically supplied into the humidifying tank  41 . Accordingly, the water level inside the humidifying tank  41  can be kept constant. Therefore, the water can be continuously supplied to the humidifier  40  from the water supply container  71 , and the humidified air can be stably and continuously supplied to the baby accommodation chamber  16 . The water supply unit  70  can be configured using a water pump. 
     In addition, the water level sensor  45  which detects the water level of the water stored inside the humidifying tank  41  is provided. Accordingly, when the water level drops below a predetermined water level, a warning is issued so as to inform the operator of the abnormal water level inside the humidifying tank  41 . Accordingly, the operator can take various safety measures by reliably supplying the water into the humidifying tank  41  or by forcibly stopping the heating performed by the humidifier  40 . Therefore, the no-water heating can be prevented, and the humidified air can be stably supplied to the baby accommodation chamber  16 . 
     The present invention is not limited to the configurations of the above-described embodiment. With regard to the detailed configurations, various modifications can be added thereto within the scope not departing from the gist of the present invention. 
     INDUSTRIAL APPLICABILITY 
     The air can be continuously humidified, and the hygienic air can be stably supplied to the baby accommodation chamber.