Patent Publication Number: US-2023145956-A1

Title: Air supply device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to Japanese Patent Application No. 2021-183359 filed in Japan on Nov. 10, 2021. The entire disclosure of Japanese Patent Application No. 2021-183359 is hereby incorporated herein by reference. 
     BACKGROUND 
     Field of the Invention 
     This invention generally relates to an air supply device. More specifically, this invention relates to an air supply device provided with a flow path switching unit. 
     Background Information 
     Generally, an air supply device is equipped with a flow path switching unit (see, for example, Japanese Laid-Open Patent Application Publication No. 2000-1977 (Patent Literature 1)). 
     The above-mentioned Patent Literature 1 discloses a device equipped with an air pump and a controller. In Patent Literature 1, it is configured such that a rotary valve housed in the controller is rotated to supply air from the air pump to an air mattress or exhaust air from the air mattress. In Patent Literature 1, a groove which serves as a flow path when supplying air is formed on the inner circumference of the rotary valve, and a groove which serves as a flow path when exhausting air is formed on the outer circumference of the rotary valve. 
     SUMMARY 
     However, when a plurality of grooves are provided in a flow path switching unit (e.g., a rotary valve), as in the above-mentioned Patent Literature 1, there is a problem that the flow path switching unit becomes larger and the air supply device becomes larger because the grooves are provided on the outer circumference. 
     One object of this disclosure is to provide an air supply device capable of suppressing enlargement of the flow path switching unit. 
     In view of the state of the known technology, an air supply device according to an aspect of this disclosure comprises an enclosure, a pump, and a flow path switching unit. The enclosure has a sealed interior space for storing air therein. The pump is provided outside the enclosure. The pump is configured to supply air to the interior space of the enclosure. The flow path switching unit including a pedestal part mounted inside the enclosure, a rotating part rotatably mounted on the pedestal part, the rotating part having an enclosure interior space communication portion and a groove portion, and a drive unit configured to rotate the rotating part. The enclosure includes an air supply port for supplying air from the pump to the interior space of the enclosure, an air discharge port for discharging air from the groove portion of the rotating part, and at least one object connection port for supplying air to or exhausting air from at least one object. The pedestal part includes at least one first hole that is communicated to the at least one object connection port, and a second hole that is communicated to the air discharge port. The enclosure interior space communication portion is communicated to the air supply port through the interior space of the enclosure. The groove portion is separated from the enclosure interior space communication portion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the attached drawings which form a part of this original disclosure: 
         FIG.  1    is a diagram showing an example of an air supply device. 
         FIG.  2    is a circuit diagram of the air supply device in a first embodiment. 
         FIG.  3    is a diagram showing an example in which first holes and a second hole are arranged on a bottom of an enclosure in the first embodiment. 
         FIG.  4    is a cross-sectional view showing the structure of a flow path switching unit in the first embodiment. 
         FIG.  5    is a diagram showing an example of a pedestal part in the first embodiment. 
         FIG.  6    is a diagram showing an example of a rotating part. 
         FIG.  7    is a diagram showing a state in which the flow path switching unit and objects (bag-shaped members) are connected in the first embodiment. 
         FIG.  8    is a diagram illustrating a gear portion. 
         FIG.  9    is a diagram showing an example of a detector plate in the first embodiment. 
         FIG.  10    is a diagram illustrating an air flow when supplying air to an object (a bag-shaped member) in the first embodiment. 
         FIG.  11    is a diagram illustrating an air flow when exhausting air from the object (the bag-shaped member) in the first embodiment. 
         FIG.  12    is a diagram illustrating a maintained state in which the objects (the bag-shaped members) are maintained in an inflated state or in a deflated state in the first embodiment. 
         FIG.  13    is a control flow of a control unit when supplying air to the object (the bag-shaped member). 
         FIG.  14    is a control flow of the control unit when exhausting air from the object (the bag-shaped member). 
         FIG.  15    is a circuit diagram of an air supply device in a second embodiment. 
         FIG.  16    is a diagram showing an example in which first holes, a second hole and third holes are arranged on a bottom of an enclosure in the second embodiment. 
         FIG.  17    is a cross-sectional view showing the structure of a flow path switching unit in the second embodiment. 
         FIG.  18    is a diagram showing an example of a pedestal part in the second embodiment. 
         FIG.  19    is a diagram showing a state in which the flow path switching unit and objects (bag-shaped members) are connected in the second embodiment. 
         FIG.  20    is a diagram showing an example of a detector plate in the second embodiment. 
         FIG.  21    is a diagram illustrating air flow when supplying air to an object (a bag-shaped member) in the second embodiment. 
         FIG.  22    is a diagram illustrating air flow when exhausting air from the object (the bag-shaped member) in the second embodiment. 
         FIG.  23    is a diagram illustrating a maintained state in which the objects (the bag-shaped members) are maintained in an inflated state or in a deflated state in the second embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Selected embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. 
     First Embodiment 
     First, with reference to  FIG.  1   , the configuration of an air supply device  100  according to a first embodiment will be described. 
     As shown in  FIG.  1   , the air supply device  100  according to the first embodiment is a device for supplying air to an article  300 . Specifically, the air supply device  100  is a device for inflating at least one bag-shaped member  10  (e.g., a plurality of bag-shaped members  10  in  FIG.  1   ) within the article  300  by supplying air to the bag-shaped members  10 , and for deflating the bag-shaped members  10  by discharging air from the bag-shaped members  10 . The article  300  is, for example, an air mattress, a massage chair, or the like. The bag-shaped members  10  are examples of “objects” of the present disclosure. 
     As shown in  FIG.  2   , the air supply device  100  comprises an enclosure  1 , a pump  2 , and a flow path switching unit  3 . In the illustrated embodiment, the air supply device  100  comprises a control unit or controller  4 , a main body  5 , at least one pressure sensor  6  (e.g., a plurality of pressure sensors  6  in  FIG.  2   ), and a drive unit or driver  8 . 
     The enclosure  1  made of a resin. The enclosure  1  is, for example, a box of a rectangular or cubic shape. The enclosure  1  has a sealed interior space  1   a  (see  FIG.  4   ). The flow path switching unit  3  is mounted inside the enclosure  1 . The enclosure  1  is arranged inside the main body  5 . 
     The enclosure  1  enables air to be stored in the interior space  1   a  (see  FIG.  4   ) and has the function of a buffer tank. The buffer tank is a tank whose volume is set to be larger than an inlet to which a pipe is connected. The buffer tank is a tank to reduce fluctuation of air pressure in the buffer tank by the larger volume and to suppress pulsation of outlet pressure. 
     As shown in  FIGS.  3  and  4   , with the enclosure  1 , the flow path switching unit  3  is mounted on a bottom  1   b . The bottom  1   b  of the enclosure  1  is provided with an air supply port  11 , an air discharge port  12 , and at least one object connection port  13  (e.g., a plurality of object connection ports  13  in  FIG.  3   ). 
     The air supply port  11  is a hole for supplying air from the pump  2  into the interior space  1   a  of the enclosure  1 . A first pipe  30   a  is connected to the air supply port  11  so as not to form a gap to communicate an air outlet port of the pump  2  and the air supply port  11  (see  FIG.  7   ). One air supply port  11  is provided in the enclosure  1 . 
     The air discharge port  12  is a hole for discharging air. A second pipe  30   b  is connected to the air discharge port  12  so as not to form a gap to discharge air outside the enclosure  1  without using the pump  2  (natural exhaust) (see  FIG.  7   ). One air discharge port  12  is provided in the enclosure  1 . A silencer  7  (see  FIG.  2   ) is attached to one end of the second pipe  30   b  that opens to the outside. The silencer  7  is, for example, a cover member made of urethane. The silencer  7  is a device for muffling sound when exhausting air from the air discharge port  12 . 
     The object connection ports  13  are holes for supplying air to the bag-shaped members  10  or exhausting air from the bag-shaped members  10 . Third pipes  30   c  are connected to the object connection ports  13 , respectively, so as not to form a gap to communicate the bag-shaped members  10  and the object connection ports  13  (see  FIG.  7   ). The number of the object connection ports  13  may be the same or different from the number of the bag-shaped members  10 . In the first embodiment, four object connection ports  13  and four bag-shaped members  10  are provided, respectively. 
     As shown in  FIG.  2   , the pump  2  is provided inside the main body  5 . The pump  2  is also provided outside the enclosure  1 . The pump  2  is configured to supply air to the interior space  1   a  (see  FIG.  4   ) of the enclosure  1 . The pump  2  is a driving source for distributing air in the air supply device  100 . In the illustrated embodiment, the pump  2  is an electric air pump, for example. The pump  2  is stopped when rotating a rotating part  32  of the flow path switching unit  3 , as described below. 
     As shown in  FIG.  4   , the flow path switching unit  3  has a pedestal part or pedestal  31  and the rotating part or rotor  32 . The flow path switching unit  3  is configured to switch flow paths for supplying air to the bag-shaped members  10  (see  FIG.  2   ) and flow paths for exhausting air from the bag-shaped members  10 . The flow path switching unit  3  is also configured to switch or select a bag-shaped member  10  for exhausting or supplying air from among the bag-shaped members  10 . In the vertical direction of the enclosure  1 , the top side is referred to as Z 1  and the bottom  1   b  side is referred to as Z 2 . 
     As shown in  FIGS.  4  and  5   , the pedestal part  31  is mounted inside the enclosure  1 . When viewed from the Z 1  side to the Z 2  side, the pedestal part  31  has a circular shape. The pedestal part  31  is made of resin. The pedestal part  31  is mounted inside the enclosure  1  so as to cover the air discharge port  12  and the object connection ports  13 . The pedestal part  31  includes at least one first hole  31   a  (e.g., a plurality of first holes  31   a  in  FIG.  5   ) and a second hole  31   b.    
     When viewed from the Z 1  side to the Z 2  side, the first holes  31   a  are provided at the same positions as the object connection ports  13  (see  FIG.  3   ) provided in the enclosure  1 . The first holes  31   a  (the object connection ports  13 ) are circumferentially arranged along an outer portion of the pedestal part  31  at a predetermined interval. The first holes  31   a  (the object connection ports  13 ) are arranged at a predetermined distance from a rotational center of the rotating part  32 . In the first embodiment, four first holes  31   a  (four object connection ports  13 ) are provided. 
     When viewed from the Z 1  side to the Z 2  side, the second hole  31   b  is provided at the same position as the air discharge port  12  (see  FIG.  3   ) provided in the enclosure  1 . The second hole  31   b  (the air discharge port  12 ) is provided on an inner side closer to the center than the first holes  31   a.    
     As shown in  FIG.  6   , the rotating part  32  is mounted so as to cover an upper surface of the pedestal part  31  (see  FIG.  4   ). The rotating part  32  is rotatably mounted on the pedestal part  31 . A lower surface of the rotating part  32  is in contact with the upper surface of the pedestal part  31 . Specifically, the lower surface of the rotating part  32  airtightly contacts with the upper surface of the pedestal part  31  such that air does not flow between the lower surface of the rotating part  32  and the upper surface of the pedestal part  31 . The rotating part  32  rotates while the lower surface remains in contact with the upper surface of the pedestal part  31 . 
     The rotating part  32  is made of resin. The rotating part  32  has a circular shape when viewed from the Z 2  side to the Z 1  side. The rotating part  32  approximately has the same size as the pedestal part  31 . The rotating part  32  switches between an air exhaust state, an air supply state, and a maintained state by rotation. The maintained state is a state in which air supply and exhaust is stopped and an inflated state or a deflated state of the bag-shaped members  10  is maintained. The direction of rotation when switching between the air exhaust state, the air supply state, and the maintained state may be the same or different. The rotating part  32  has an enclosure interior space communication portion  32   a  and a groove portion  32   b . The enclosure interior space communication portion  32   a  and the groove portion  32   b  open toward the pedestal part  31  (the Z 2  side), respectively, and form an air flow path. Specifically, the first holes  31   a  and the second hole  31   b  provided in the pedestal part  31  and the enclosure interior space communication portion  32   a  and the groove portion  32   b  of the rotating part  32  form a flow path. The portion of the rotating part  32  forming the enclosure interior space communication portion  32   a  and the groove portion  32   b  is hereinafter referred to as a wall portion  32   f.    
     The enclosure interior space communication portion  32   a  is provided on an outer portion of the rotating part  32 . The enclosure interior space communication portion  32   a  is communicated to the air supply port  11  through the interior space  1   a  of the enclosure  11 . Specifically, the enclosure interior space communication portion  32   a  opens toward the pedestal part  31  and the enclosure  1  (see  FIG.  4   ) so as to be communicated to the air supply port  11  through the interior space  1   a  of the enclosure  1 . The enclosure interior space communication portion  32   a  opens in an outer surface (an outer circumferential surface) of the rotating part  32 . The enclosure interior space communication portion  32   a  has an elliptical shape that is inwardly depressed when viewed from the Z 1  side to the Z 2  side. In the illustrated embodiment, the enclosure interior space communication portion  32   a  is formed by a notch, but can be formed by a through hole. 
     As shown in  FIG.  7   , the enclosure interior space communication portion  32   a  is disposed on the outer portion of the rotating part  32  so as to be communicated to the first holes  31   a . When supplying air, the enclosure interior space communication portion  32   a  rotates so that a portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is communicated to one of the first holes  31   a  provided in the pedestal part  31 , and a flow path is formed between the first hole  31   a  and the air supply port  11 . The rotating part  32  selectively communicates one of the first holes  31   a  to the enclosure interior space communication portion  32   a  depending on the rotational position. 
     When exhausting air, the rotating part  32  rotates so that the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is not communicated to any one of the first holes  31   a  and the second hole  31   b . On the other hand, a portion of the groove portion  32   b  of the rotating part  32  that opens toward the pedestal part  31  (the Z 2  side) is communicated to the first hole  31   a  and the second hole  31   b  provided in the pedestal part  31  to form a flow path. With this configuration, a flow path is formed between the first hole  31   a  and the second hole  31   b  to discharge air from the bag-shaped member  10  to the outside. The rotating part  32  selectively communicates one of the first holes  31   a  to the groove portion  32   b  depending on the rotational position. 
     During the maintained state, the rotating part  32  rotates so that the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is not communicated to the first holes  31   a  provided in the pedestal part  31 . In other words, the first holes  31   a  are blocked and air is not supplied to the bag-shaped members  10  nor exhausted from the bag-shaped members  10 . 
     As shown in  FIG.  6   , the groove portion  32   b  is provided on the inner portion of the rotating part  32 . The groove portion  32   b  is separated from the enclosure interior space communication portion  32   a . The groove portion  32   b  is not communicated to the enclosure interior space communication portion  32   a . The groove portion  32   b  does not open, except for in a surface on the Z 2  side, and does not open in the outer circumferential surface since it is surrounded by the wall portion  32   f . The groove portion  32   b  has a circular portion  32   c  and a protruding portion  32   d . In particular, the groove portion  32   b  has the circular portion  32   c  and the protruding portion  32   d  that is communicated to the circular portion  32   c  and outwardly protrudes from the circular portion  32   c . The protruding portion  32   d  is located opposite to the enclosure interior space communication portion  32   a  with respect to a rotational center of the rotating part  32 . 
     As shown in  FIG.  7   , the circular portion  32   c  can be communicated to the second hole  31   b . On the other hand, when supplying air, the protruding portion  32   d  rotates so as not to be communicated to the first holes  31   a . Therefore, when supplying air, the first holes  31   a  are not communicated to the second hole  31   b . As a result, it is possible to prevent that the supplied air is discharged to the outside. 
     When exhausting air, the protruding portion  32   d  rotates so as to be communicated to the first hole  31   a . As a result, the first hole  31   a  and the second hole  31   b  are communicated. The rotating part  32  selectively communicates one of the first holes  31   a  to the second hole  31   b  depending on the rotational position. 
     In the maintained state, the protruding portion  32   d  rotates so as not to be communicated to the first holes  31   a . Thereby, the first holes  31   a  are blocked by the wall portion  32   f , and the first holes  31   a  are not communicated to the second hole  31   b . As a result, air is neither supplied to nor exhausted from the bag-shaped members  10 . 
     As shown in  FIG.  8   , the rotating part  32  includes a gear portion  32   e  formed on the outer circumferential surface of the rotating part  32 . The gear portion  32   e  engages with a gear  8   b  of the drive unit  8  (see  FIG.  4   ), as described later. The gear portion  32   e  has a larger diameter and a larger number of teeth than the gear  8   b.    
     As shown in  FIG.  4   , the drive unit  8  is configured to switch the flow path switching unit  3 . The drive unit  8  is provided with a motor  8   a  and the gear  8   b . The drive unit  8  may comprise a geared motor. The drive unit  8  rotates the gear  8   b  by the motor  8   a  to rotate the rotating part  32 . Specifically, the rotating part  32  rotates in a state in which the gear  8   b  and the gear portion  32   e  are engaged with each other. Thereby, the number of teeth slows down the rotation speed and the gear portion  32   e  functions as a reduction gear. In the first embodiment, the motor  8   a  is provided inside the enclosure  1 , but the motor  8   a  can also be provided outside the enclosure  1 . When the motor  8   a  is provided outside the enclosure  1 , a sealing member may be added to a gap between the enclosure  1  and a rotation shaft of the motor  8   a  to minimize air leakage from the gap between the rotation shaft and the enclosure  1 . 
     As shown in  FIGS.  4  and  9   , the air supply device  100  includes a phase detection unit or phase detector  9 . The phase detection unit  9  is, for example, a detector plate  91  including an encoder with slits formed at a predetermined interval. With the detector plate  91 , a first detection portion  91   a  and a second detection portion  91   b  are attached. The first detection portion  91   a  and the second detection portion  91   b  each have a light emitter and a detector, respectively. The detector plate  91  also has a first slit  91   c  indicating an initial position, and second slits  91   d  at each predetermined angle. The second slits  91   d  are provided corresponding to the first holes  31   a  of the pedestal part  31  and positions of the maintained state. In the first embodiment, a total of six second slits  91   d , four corresponding to the four first holes  31   a  and two for maintained state positions, are provided at equal intervals (e.g., every 36 degrees). Here, slits are not provided at symmetrical positions of the detector plate  91  relative to the positions of the first holes  31   a  with respect to the center. The initial position is detected by the first detection portion  91   a  detecting, by the detector, the light from the light emitter passing through the first slit  91   c . Also, a rotational angle is detected by the number of times the second detection portion  91   b  detects the light passing through the second slits  91   d . Depending on the positions of the slits of the encoder, the air supply state, the air exhaust state, and the maintained state can be switched. Here, the phase detection unit  9  may be attached to the flow path switching unit  3  or may be away from the flow path switching unit  3 . The phase detection unit  9  may be configured by, for example, a sensor including a detection circuit, as long as it is capable of acquiring a phase change (degree of rotation) of the rotating part  32  of the flow path switching unit  3 . 
     As shown in  FIG.  2   , the control unit  4  is configured to control the pump  2  and the rotating part  32 . The control unit  4  is configured to control the pump  2  and the rotating part  32  by receiving an external input. The control unit  4  is configured to supply air to the bag-shaped members  10  or exhaust air from the bag-shaped members  10 . The control unit  4  is also configured to stop rotation of the rotating part  32  based on detection result by the detector plate  91 . The control unit  4  is also configured to stop driving of the pump  2  based on the air pressure of the interior space  1   a  of the enclosure  1  measured by the pressure sensors  6  and to switch from the air supply state or the air exhaust state to the maintained state by rotating the rotating part  32 . The control unit  4  is also configured to switch the bag-shaped members  10  for supplying and exhausting air according to an external input. In the illustrated embodiment, the control unit or controller  4  includes a processor or electrical controller which is a hardware device capable of executing a software program, and does not include a human. In the illustrated embodiment, the control unit  4  includes a CPU. However, in some cases, the control unit  4  can be configured to comprise, instead of the CPU or in addition to the CPU, programmable logic devices such as a DSP (Digital Signal Processing or Processor), an FPGA (Field Programmable Gate Array), and the like. In addition, the control unit  4  can include a plurality of processors or CPUs that execute the processing sequences of the present disclosure together. In the illustrated embodiment, the control unit  4  is electrically or operatively connected to the pump  2 , and is configured to control the pump  2 . The control unit  4  is electrically or operatively connected to the pressure sensors  6 , and is configured to control the pump  2  or the drive unit  8  based on the detection results of the pressure sensors  6 . The control unit  4  is electrically or operatively connected to the drive unit  8 , and is configured to control the drive unit  8  to rotate the rotating part  32 . The control unit  4  is electrically or operatively connected to the phase detection unit  9 , and is configured to control the pump  2  or the drive unit  8  based on the detection result of the phase detection unit  9 . 
     The enclosure  1 , the pump  2 , the control unit  4 , and the pressure sensors  6  are arranged inside the main body. The main body  5  is, for example, a box made of resin. The main body  5  is also provided with a power supply (not shown) for driving the pump  2  and the flow path switching unit  3 . Also, the power supply supplies electric power to the control unit  4 , the pressure sensors  6  and the phase detection unit  9 , as needed and/or desired. 
     The pressure sensors  6  measure the pressure of air supplied to the interior space  1   a  of the enclosure  1  or exhausted from the interior space  1   a  of the enclosure  1 . The pressure sensors  6  are provided to the first pipe  30   a  (see  FIG.  7   ) connected between the air supply port  11  and the pump  2  and to the second pipe  30   b  (see  FIG.  7   ) connected between the air discharge port  12  and the silencer  7 . When the pressure sensor  6  on the first pipe  30   a  detects a pressure equal to or higher than a predetermined value, the control unit  4  is configured to stop the pump  2 . Also, when the pressure sensor  6  on the second pipe  30   b  detects a pressure below a predetermined value, the control unit  4  is configured to stop the pump  2 . The predetermined values of the two pressure sensors  6  are different, and for example, the predetermined value for the pressure sensor  6  on the first pipe  30   a  is a positive value and the predetermined value for the pressure sensor  6  on the second pipe  30   b  is 0 or a negative value. 
     (Arrangement of Rotating Part when Supplying Air) 
     The arrangement of the rotating part  32  when supplying air will be described based on  FIG.  10   . When supplying air to one of the bag-shaped members  10 , the enclosure interior space communication portion  32   a  is arranged at a position to be communicated to corresponding one of the object connection ports  13  via corresponding one of the first holes  31   a . Also, the circular portion  32   c  of the groove portion  32   b  is communicated to the air discharge port  12  via the second hole  31   b . The protruding portion  32   d  of the groove portion  32   b  is not communicated to the first holes  31   a  and the second hole  31   b . Thus, the corresponding one of the first holes  31   a  is located in the enclosure interior space communication portion  32   a  when supplying air to the one of the bag-shaped members  10 . In particular, the corresponding one of the first holes  31   a  is located in the enclosure interior space communication portion  32   a  and the second hole  31   b  is located in the circular portion  32   c  when supplying air to the one of the bag-shaped members  10 . 
     The air drawn into the pump  2  is supplied from the pump  2  to the interior space  1   a  of the enclosure  1  through the air supply port  11 . The air supplied to the interior space  1   a  of the enclosure  1  is supplied to the first hole  31   a  (the object connection port  13 ) through the enclosure interior space communication portion  32   a . With this configuration, the air can be supplied to the bag-shaped member  10 . 
     (Arrangement of Rotating Part when Exhausting Air) 
     The arrangement of the rotating part  32  when exhausting air will be described based on  FIG.  11   . When exhausting air from one of the bag-shaped members  10 , the groove portion  32   b  is arranged at a position where the circular portion  32   c  is communicated to the air discharge port  12  via the second hole  31   b  and the protruding portion  32   d  is communicated to corresponding one of the object connection ports  13  via corresponding one of the first holes  31   a . Thus, the corresponding one of the first holes  31   a  and the second hole  31   b  are located in the groove portion  32   b  when exhausting air from the one of the bag-shaped members  10 . In particular, the corresponding one of the first holes  31   a  is located in the protruding portion  32   d  and the second hole  31   b  is located in the circular portion  32   c  when exhausting air from the one of the bag-shaped members  10 . With this configuration, air flows from the bag-shaped member  10  to the object connection port  13 . Then, the air flows from the object connection port  13  to the groove portion  32   b . The air flowing into the groove portion  32   b  is then discharged to the outside by the air discharge port  12 . The enclosure interior space communication portion  32   a  is not communicated to the first holes  31   a  and the second hole  31   b . Even if the pump  2  is driven while exhausting air, the air is stored inside the enclosure  1  and is not supplied to the bag-shaped member  10 . Thus, the pump  2  can be driven while exhausting air. However, to reduce the power consumption, the drive of the pump  2  may be stopped while exhausting air. 
     (Arrangement of Rotating Part in Maintained State) 
     As shown in  FIG.  12   , in the maintained state of the inflated or deflated state of the bag-shaped members  10  for which supplying and exhausting air is stopped, the enclosure interior space communication portion  32   a  is not communicated to the first holes  31   a . In addition, with the groove portion  32   b , the circular portion  32   c  is communicated to the second hole  31   b , but the groove portion  32   b  (the circular portion  32   c  and the protruding portion  32   d ) is not communicated to the first holes  31   a . Thus, the first holes  31   a  are blocked by the rotating part  32  when maintaining the inflated state or the deflated state of the bag-shaped members  10 . Therefore, a flow path between the first holes  31   a  and the second hole  31   b  is not formed. With this configuration, air is neither supplied to the bag-shaped members  10  nor discharged from the bag-shaped members  10 , and the bag-shaped members  10  can maintain the inflated state or the deflated state. 
     (Control when Supplying Air) 
     The control of the control unit  4  when supplying air will be described based on  FIG.  13   . First, as step S 1 , the control unit  4  receives an input indicating a bag-shaped member  10  as an object or target for supplying air. The input is, for example, an input by a remote controller or an operation button. 
     In step S 2 , the control unit  4  stops the pump  2 . In step S 3 , the control unit  4  controls the drive unit  8  to rotate the rotating part  32  at a predetermined angle or at a predetermined interval by driving the motor  8   a  of the drive unit  8 . The predetermined angle of the rotating part  32  is set in accordance with the interval at which the first holes  31   a  are arranged by using a position at which the first detection portion  91   a  and the second detection portion  91   b  both detect light as the initial position (i.e., 0 degrees). The initial position is also a position in which air supply and exhaust to all the bag-shaped members  10  are also stopped. When the rotating part  32  is located at the initial position, the control unit  4  rotates the rotating part  32  to the predetermined angle. Specifically, the control unit  4  rotates the rotating part  32  until the second detection portion  91   b  detects light a predetermined number of times corresponding to the predetermined angle. When the rotating part  32  has been rotated from the initial position (e.g., when air is being supplied to other bag-shaped member  10 ), the control unit  4  rotates the rotating part  32  by an angular difference obtained by subtracting a rotational angle that has already been rotated from an angle between the initial position and a position corresponding to the target bag-shaped member  10 . Specifically, the control unit  4  controls the drive unit  8  to rotate the rotating part  32  until the second detection portion  91   b  detects light a predetermined number of times corresponding to the angular difference. 
     In step S 4 , the control unit  4  performs the next control differently depending on whether the rotational angle of the rotating part  32  is the predetermined angle or not. Specifically, the control unit  4  acquires the detection result detected by the detector plate  91 , and if the rotational angle of the rotating part  32  is the predetermined angle, or in other words, if the second detection portion  91   b  detects light the predetermined number of times, then it proceeds to step S 5 . On the other hand, if the second detection portion  91   b  has not detected light the predetermined number of times, then step S 4  is repeated until the predetermined angle is reached (until light is detected the predetermined number of times). 
     In step S 5 , the control unit  4  stops the motor  8   a  of the drive unit  8  to stop the rotation of the rotating part  32 . 
     In step S 6 , the control unit  4  drives the pump  2  to supply air to the bag-shaped member  10 . In step S 7 , the control unit  4  changes the control depending on whether or not the pressure detected by the pressure sensor  6  provided to the first pipe  30   a  is more than or equal to the predetermined value. If it is more than or equal to the predetermined value, then it proceeds to step S 8  and the control unit  4  stops the pump  2 . If it is less than the predetermined value, then step S 7  is repeated until it becomes more than or equal to the predetermined value. 
     After stopping the pump  2  in step S 8 , in step S 9 , the control unit  4  controls the drive unit  8  to rotate the rotating part  32  to the position for the maintained state. In step S 10 , the control unit  4  performs the next control differently depending on whether the rotational angle of the rotating part  32  is the predetermined angle or not. Specifically, the control unit  4  acquires the detection result detected by the detector plate  91 , and if the rotational angle of the rotating part  32  is the predetermined angle, then it proceeds to step S 11 . A case in which the rotational angle of the rotating part  32  is the predetermined angle means a case in which the second detection portion  91   b  detects light the predetermined number of times. On the other hand, if the second detection portion  91   b  has not detected light the predetermined number of times, then step S 10  is repeated until the predetermined angle is reached (until light is detected the predetermined number of times). In step S 11 , the control unit  4  stops the motor  8   a  of the drive unit  8  to stop the rotation of the rotating part  32 . With this configuration, the bag-shaped member  10  can maintain the inflated state. 
     (Control when Exhausting Air) 
     The control of the control unit  4  when exhausting air will be described based on  FIG.  14   . First, as step S 21 , the control unit  4  receives an input indicating a bag-shaped member  10  as an object or target for exhausting air. 
     In step S 22 , the control unit  4  stops the pump  2 . In step S 23 , the control unit  4  controls the drive unit  8  to rotate the rotating part  32  at a predetermined angle or at a predetermined interval by driving the motor  8   a  of the drive unit  8 . The predetermined angle of the rotating part  32  is set in accordance with the interval at which the first holes  31   a  are arranged by using a position at which the first detection portion  91   a  and the second detection portion  91   b  both detect light as the initial position (i.e., 0 degrees). The initial position is also a position in which air supply and exhaust to all the bag-shaped members  10  are also stopped. When the rotating part  32  is located at the initial position, the control unit  4  rotates the rotating part  32  to the predetermined angle. Specifically, the control unit  4  rotates the rotating part  32  until the second detection portion  91   b  detects light a predetermined number of times corresponding to the predetermined angle. When the rotating part  32  has been rotated from the initial position (e.g., when air is being exhausted from other bag-shaped member  10 ), the control unit  4  rotates the rotating part  32  by an angular difference obtained by subtracting a rotational angle that has already been rotated from an angle between the initial position and a position corresponding to the target bag-shaped member  10 . Specifically, the control unit  4  controls the drive unit  8  to rotate the rotating part  32  until the second detection portion  91   b  detects light a predetermined number of times corresponding to the angular difference. 
     In step S 24 , the control unit  4  performs the next control differently depending on whether the rotational angle of the rotating part  32  is the predetermined angle or not. Specifically, the control unit  4  acquires the detection result detected by the detector plate  91 , and if the rotational angle of the rotating part  32  is the predetermined angle, or in other words, if the second detection portion  91   b  detects light the predetermined number of times, then it proceeds to step S 25 . On the other hand, if the second detection portion  91   b  has not detected light the predetermined number of times, then step S 24  is repeated until the predetermined angle is reached (until light is detected the predetermined number of times). 
     In step S 25 , the control unit  4  stops the motor  8   a  of the drive unit  8  to stop the rotation of the rotating part  32 . 
     In step S 27 , the control unit  4  changes the control depending on whether or not the pressure detected by the pressure sensor  6  provided to the second pipe  30   b  is less than the predetermined value. If it is less than the predetermined value, then it proceeds to step S 29 . If it is more than or equal to the predetermined value, then step S 27  is repeated until it becomes less than the predetermined value. In the illustrated embodiment, the drive of the pump  2  in step S 26  and the stop of the pump  2  in step S 28  shown in  FIG.  14    will not be performed. However, the drive of the pump  2  in step S 26  and the stop of the pump  2  in step S 28  shown in  FIG.  14    will be performed by the configuration according to a second embodiment, as described later. 
     In step S 29 , the control unit  4  controls the drive unit  8  to rotate the rotating part  32  to the position for the maintained state. In step S 30 , the control unit  4  performs the next control differently depending on whether the rotational angle of the rotating part  32  is the predetermined angle or not. Specifically, the control unit  4  acquires the detection result detected by the detector plate  91 , and if the rotational angle of the rotating part  32  is the predetermined angle, or in other words, if the second detection portion  91   b  detects light the predetermined number of times, then it proceeds to step S 31 . On the other hand, if the second detection portion  91   b  has not detected light the predetermined number of times, then step S 30  is repeated until the predetermined angle is reached (until the second detection portion  91   b  detects light the predetermined number of times). In step S 31 , the control unit  4  stops the motor  8   a  of the drive unit  8  to stop the rotation of the rotating part  32 . With this configuration, the bag-shaped member  10  can maintain the deflated state. 
     Effects of First Embodiment 
     In the first embodiment, the following effects can be obtained. 
     In the first embodiment, as described above, the air supply device  100  comprises the enclosure  1 , the pump  2 , and the flow path switching unit  3 . The enclosure  1  has the sealed interior space  1   a  for storing air therein. The pump  2  is provided outside the enclosure  1 . The pump  2  is configured to supply air to the interior space  1   a  of the enclosure  1 . The flow path switching unit  3  includes the pedestal part  31  mounted inside the enclosure  1 , the rotating part  32  rotatably mounted on the pedestal part  31 , the rotating part  32  having the enclosure interior space communication portion  32   a  and the groove portion  32   b , and the drive unit  8  configured to rotate the rotating part  32 . The enclosure  1  includes the air supply port  11  for supplying air supplied from the pump  2  to the interior space  1   a  of the enclosure  1 , the air discharge port  12  for discharging air from the groove portion  32   b  of the rotating part  32 , and the object connection ports  13  for supplying air to or exhausting air from the bag-shaped members  10 . The pedestal part  31  includes the first holes  31   a  that are communicated to the object connection ports  13 , and the second hole  31   b  that is communicated to the air discharge port  12 . The enclosure interior space communication portion  32   a  is communicated to the air supply port  11  through the interior space  1   a  of the enclosure  1 . The groove portion  32   b  is separated from the enclosure interior space communication portion  32   a.    
     The enclosure interior space communication portion  32   a  includes a notch or a through hole that is provided on the outer portion of the rotating part  32 . The notch or the through hole opens toward the pedestal part  31  and the enclosure  1  so as to be communicated to the air supply port  11  through the interior space  1   a  of the enclosure  1 . The groove portion  32   b  opens toward the pedestal part  31  so as not to be directly communicated to the enclosure interior space communication portion  32   a.    
     With this configuration, the rotating part  32  includes the enclosure interior space communication portion  32   a  on the outer portion of the rotating part  32 . Therefore, the sealed interior space  1   a  of the enclosure  1  can be used as a flow path for supplying air or exhausting air, and thus there is no need to provide a groove for forming a flow path in an outer circumference of the rotating part  32 . With this configuration, enlargement of the flow path switching unit  3  can be suppressed. As a result, enlargement of the air supply device  100  can be suppressed. 
     In the first embodiment, as described above, the air supply device further comprises the control unit  4  configured to control the drive unit  8  to rotate the rotating part  32  to the position at which the position of one of the first holes  31   a  and the position of the enclosure interior space communication portion  32   a  coincide to each other when supplying air to one of the bag-shaped members  10 , and the control unit  4  being configured to control the drive unit  8  to rotate the rotating part  32  to the position at which the one of the first holes  31   a  and the second hole  31   b  are communicated to each other through the groove portion  32   b  when exhausting air from the one of the bag-shaped members  10 . With this configuration, when supplying air to the one of the bag-shaped members  10 , the enclosure interior space communication portion  32   a  and the one of the first holes  31   a  are communicated to each other and a flow path is formed from the interior space  1   a  of the enclosure  1  to the one of the bag-shaped members  10 . Thus, air inside the enclosure  1  can be supplied to the one of the bag-shaped members  10 . Also, when exhausting air from the one of the bag-shaped members  10 , the one of the first holes  31   a  and the second hole  31   b  are communicated to each other and a flow path is formed from the one of the bag-shaped members  10  to the air discharge port  12 . Thus, the air can be exhausted from the one of the bag-shaped members  10 . 
     In the first embodiment, as described above, the control unit  4  is configured to switch the bag-shaped members  10  for supplying and exhausting air by rotating the rotating part  32  at the predetermined angle or at the predetermined interval. With this configuration, switching of the bag-shaped members  10  can be easily performed by setting the predetermined angle or the predetermined interval in accordance with the positions of the first holes  31   a  and the second hole  31   b.    
     In the first embodiment, as described above, the air supply device  100  further comprises the pressure sensors  6  for measuring the pressure of air supplied to the interior space  1   a  of the enclosure  1  and exhausted from the interior space  1   a  of the enclosure  1 . When supplying air to the one of the bag-shaped members  10 , the control unit  4  is configured to control the drive unit  8  to rotate the rotating part  32  to the position at which no flow path is formed between the first holes  31   a  and the second hole  31   b  while the pressure detected by one of the pressure sensors  6  is higher than or equal to the predetermined value. With this configuration, the control unit  4  can acquire that air has been sufficiently supplied to the one of the bag-shaped members  10  based on the fact that air pressure in the one of the bag-shaped members  10  in a full air state has become more than or equal to the predetermined value. In addition, when the pressure detected by the one of the pressure sensors  6  is more than or equal to the predetermined value, no flow path is formed between the first holes  31   a  and the second hole  31   b . Thus, no flow path is formed from the one of the bag-shaped members  10  to the air discharge port  12 , and it is possible to prevent that air is discharged from the one of the bag-shaped members  10 . 
     In the first embodiment, as described above, when exhausting air from the one of the bag-shaped members  10 , the control unit  4  is configured to control the drive unit  8  to rotate the rotating part  32  to the position at which no flow path is formed between the first holes  31   a  and the second hole  31   b  while the pressure detected by the other one of the pressure sensors  6  is less than the predetermined value. With this configuration, by setting the predetermined value to an air pressure in the one of the bag-shaped members  10  in a sufficiently exhausted state, it is possible for the control unit  4  to acquire that air has been sufficiently exhausted from the one of the bag-shaped members  10 . Also, no flow path is formed between the first holes  31   a  and the second hole  31   b  while the pressure is less than the predetermined value. Thus, no flow path is formed from the one of the bag-shaped members  10  to the air discharge port  12 , and it is possible to prevent that air is excessively discharged from the one of the bag-shaped members  10 . 
     In the first embodiment, as described above, the control unit  4  is configured to stop the drive of the pump  2  when rotating the rotating part  32 . With this configuration, for example, when supplying air to the one of the bag-shaped members  10  by communicating the one of the first holes  31   a  to the enclosure interior space communication portion  32 , it is possible to prevent that air supplied to the interior space  1   a  of the enclosure  1  is supplied by the pump  2  to other bag-shaped member  10  by communicating other first hole  31   a  to the enclosure interior space communication portion  32   a  during rotation of the rotating part  32 . 
     In the first embodiment, as described above, the rotating part  32  includes the gear portion  32   e  formed on the outer circumferential surface of the rotating part  32 , and the control unit  4  is configured to control the drive unit  8  to rotate the rotating part  32  in a state in which the drive unit  8  and the gear portion  32   e  are engaged. With this configuration, the rotating part  32  can function as a reduction gear by varying the number of teeth between the drive unit  8  and the gear portion  32   e.    
     In the first embodiment, as described above, when viewed from the pedestal part  31  side, the enclosure interior space communication portion  32   a  has an elliptical shape inwardly depressed. The groove portion  32   b  has the circular portion  32   c  that is communicated to the second hole  31   b , and the protruding portion  32   d  that is selectively communicated to the first holes  31   a  and that outwardly protrudes from the circular portion  32   c . With this configuration, the outer circumferences of the enclosure interior space communication portion  32   a  and the groove portion  32   b  can be aligned with the outer circumferences of the first hole  31   a  and the second hole  31   b  without misalignment. Thus, it is possible to prevent supplying air to the bag-shaped member  10  or exhausting air from the bag-shaped member  10  in a state in which the first hole  31   a  and the second hole  31   b  are partially blocked by the rotating part  32 . 
     Second Embodiment 
     Referring to  FIGS.  15  to  23   , a second embodiment will be described. With an air supply device  200  in accordance with this second embodiment, unlike the first embodiment, the pedestal part  31  includes at least one third hole  31   c  (e.g., a plurality of third holes  31   c  in  FIG.  18   ). The enclosure  1  also includes at least one external air supply and exhaust port  14  (e.g., a plurality of external air supply and exhaust ports  14  in  FIG.  16   ). The parts of the second embodiment that are identical or substantially or functionally identical to the parts of the first embodiment will be given the same reference numerals, and the descriptions thereof will be omitted for the sake of brevity. 
     As shown in  FIGS.  15  and  16   , the bottom  1   b  of the enclosure  1  includes the air supply port  11 , the air discharge port  12 , the object connection ports  13 , and the external air supply and exhaust ports  14 . As also shown in  FIG.  19   , the second pipe  30   b  is connected between the air discharge port  12  and the pump  2 . Specifically, the air discharge port  12  is connected to an air intake port  2   a  of the pump  2  via the second pipe  30   b.    
     The external air supply and exhaust ports  14  are holes for supplying air from the outside of the enclosure  1  to the interior space  1   a  of the enclosure  1  or for exhausting air from the interior space  1   a  of the enclosure  1  to the outside of the enclosure. Fourth pipes  30   d  (see  FIG.  19   ) are connected to the external air supply and exhaust ports  14  so as not to form a gap. In the illustrated embodiment, the fourth pipes  30   d  merge into a single pipe, one end of which opens to the outside and is connected to the silencer  7 . The external air supply and exhaust ports  14  may be provided in the same number as the number of the bag-shaped members  10 , or may be different. In the second embodiment, four external air supply and exhaust ports  14  are provided. 
     As shown in  FIG.  19   , one ends of the fourth pipes  30   d  are connected to the external air supply and exhaust ports  14 . As shown in  FIG.  19   , the silencer  7  is connected to the one end of the single pipe, into which the fourth pipes  30   d  merge. The silencer  7  is a device for muffing sound when exhausting air from the external air supply and exhaust ports  14  and for muffing sound when supplying air to the external air supply and exhaust ports  14 . In the illustrated embodiment, one ends of the fourth pipes  30   d  merge into the single pipe. However, the one ends of the fourth pipes  30   d  can have openings that are open to the outside and can be connected to silencers  7 , respectively. 
     As shown in  FIGS.  17  and  18   , the pedestal part  31  has the first holes  31   a , the second hole  31   b , and the third holes  31   c.    
     When viewed from the Z 1  side to the Z 2  side, the third holes  31   c  are provided at the same positions as the external air supply and exhaust ports  14  (see  FIG.  16   ) provided in the enclosure  1 . The third holes  31   c  (the external air supply and exhaust ports  14 ) are circumferentially arranged along an outer portion of the pedestal part  31  at a predetermined interval. The third holes  31   c  are arranged to be point-symmetrical with the first holes  31   a  with respect to the center of the pedestal part  31  (a rotational center of the rotating part  32 ). The third holes  31   c  (the external air supply and exhaust ports  14 ) are arranged at a predetermined distance from the rotational center of the rotating part  32 . In the second embodiment, four third holes  31   c  (four external air supply and exhaust ports  14 ) are provided. 
     As shown in  FIG.  19   , the enclosure interior space communication portion  32   a  is disposed on the outer portion of the rotating part  32  so as to be communicated to the first holes  31   a  or the third holes  31   c . When supplying air, the enclosure interior space communication portion  32   a  rotates so that a portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is communicated to one of the first holes  31   a  provided in the pedestal part  31 , and a flow path is formed between the first hole  31   a  and the air supply port  11 . When supplying air, the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is not directly communicated to the third holes  31   c . At this time, one of the third holes  31   c  is located in the groove portion  32   b  that is separated from the enclosure interior space communication portion  32   a , and other third holes  31   c  are blocked by the wall portion  32   f  of the rotating part  32 . The rotating part  32  selectively communicates one of the first holes  31   a  to the enclosure interior space communication portion  32  depending on the rotational position. 
     When exhausting air, the rotating part  32  rotates so that the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is communicated to one of the third holes  31   c  provided in the pedestal part  31 , and a flow path is formed between the third hole  31   c  and the air supply port  11 . When exhausting air, the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is not directly communicated to the first holes  31   a . At this time, one of the first holes  31   a  is located in the groove portion  32   b  that is separated from the enclosure interior space communication portion  32   a , and other first holes  31   a  are blocked by the wall portion  32   f  of the rotating part  32 . The rotating part  32  selectively communicates one of the third holes  31   c  to the enclosure interior space communication portion  32   a  depending on the rotational position. 
     During the maintained state, the rotating part  32  rotates so that the portion of the enclosure interior space communication portion  32   a  that opens toward the pedestal part  31  (the Z 2  side) is not communicated to the first holes  31   a  and the third holes  31   c  provided in the pedestal part  31 . The first holes  31   a  and the third holes  31   c  are blocked by the wall portion  32   f , and air is neither supplied to the bag-shaped members  10  nor exhausted from the bag-shaped members  10 . 
     As shown in  FIG.  19   , the circular portion  32   c  can be communicated to the second hole  31   b . When supplying air, the protruding portion  32   d  rotates so as to be communicated to one of the third holes  31   c . As a result, the third hole  31   c  and the second hole  31   b  are communicated. At this time, the first holes  31   a  are not directly communicated to the protruding portion  32   d . One of the first holes  31   a  is located in the enclosure interior space communication portion  32   a  that is separated from the groove portion  32   b , and other first holes  31   a  are blocked by the wall portion  32   f . Thus, the first holes  31   a  and the second hole  31   b  are not directly communicated. The rotating part  32  selectively communicates one of the third holes  31   c  and the second hole  31   b  depending on the rotational position. 
     When exhausting air, the protruding portion  32   d  rotates so as to be communicated to one of the first holes  31   a . As a result, the first hole  31   a  and the second hole  31   b  are communicated. At this time, the third holes  31   c  are not directly communicated to the protruding portion  32   d . One of the third holes  31   c  is located in the enclosure interior space communication portion  32   a  that is separated from the groove portion  32   b , and other third holes  31   c  are blocked by the wall portion  32   f . Thus, the third holes  31   c  and the second hole  31   b  are not directly communicated. The rotating part  32  selectively communicates one of the first holes  31   a  and the second hole  31   b  depending on the rotational position. 
     During the maintained state, the protruding portion  32   d  rotates so as not to be communicated to the first holes  31   a  and the third holes  31   c . The first holes  31   a  and the third holes  31   c  are blocked by the wall portion  32   f , and the first holes  31   a  and the third holes  31   c  are not communicated to the second hole  31   b . As a result, air is neither supplied to the bag-shaped members  10  nor exhausted from the bag-shaped members  10 . 
     As shown in  FIG.  20   , in the second embodiment, a total of ten second slits  91   d , four corresponding to the four first holes  31   a , four corresponding to the four third holes  31   c  and two for maintained state positions, are provided at equal intervals (e.g., every 36 degrees). The initial position is detected by the first detection portion  91   a  detecting, by the detector, the light from the light emitter passing through the first slit  91   c . Also, a rotational angle is detected by the number of times the second detection portion  91   b  detects the light passing through the second slits  91   d . Depending on the positions of the slits of the encoder, the air supply state, the air exhaust state, and the maintained state can be switched. 
     (Arrangement of Rotating Part when Supplying Air) 
     The arrangement of the rotating part  32  when supplying air will be described based on  FIG.  21   . When supplying air to one of the bag-shaped members  10 , the enclosure interior space communication portion  32   a  is arranged at a position to be communicated to corresponding one of the object connection ports  13  via corresponding one of the first holes  31   a . Also, the circular portion  32   c  of the groove portion  32   b  is communicated to the air discharge port  12  via the second hole  31   b . The protruding portion  32   d  is arranged at a position to be communicated to corresponding one of the external air supply and exhaust ports  14  via corresponding one of the third holes  31   c . Thus, the corresponding one of the first holes  31   a  is located in the enclosure interior space communication portion  32   a  and the second hole  31   b  and the corresponding one of the third holes  31   c  are located in the groove portion  32   b  when supplying air to the one of the bag-shaped members  10 . In particular, the corresponding one of the first holes  31   a  is located in the enclosure interior space communication portion  32   a , the second hole  32   b  is located in the circular portion  32   c  and the corresponding one of the third holes  31   c  is located in the protruding portion  32   d  when supplying air to the one of the bag-shaped members  10 . 
     The air drawn from the outside by the pump  2  is supplied to the groove portion  32   b  through the external air supply and exhaust port  14 . The air passing through the groove portion  32   b  is drawn into the pump  2  through the air discharge port  12 . The air drawn into the pump  2  is supplied from the pump  2  to the interior space  1   a  of the enclosure  1  through the air supply port  11 . The air supplied to the interior space  1   a  of the enclosure  1  is supplied to the object connection port  13  through the enclosure interior space communication portion  32   a , and the air is supplied to the bag-shaped member  10 . 
     The control of the control unit  4  when supplying air is basically identical to the control shown in  FIG.  13   , and thus, the detailed description of the control will be omitted for the sake of brevity. 
     (Arrangement of Rotating Part when Exhausting Air) 
     The arrangement of the rotating part  32  when exhausting air will be described based on  FIG.  22   . When exhausting air from one of the bag-shaped members  10 , the enclosure interior space communication portion  32   a  is arranged at a position to be communicated to corresponding one of the external air supply and exhaust ports  14  via corresponding one of the third holes  31   c . The circular portion  32   c  of the groove portion  32   b  is communicated to the air discharge port  12  via the second hole  31   b . The protruding portion  32   d  is arranged at a position to be communicated to corresponding one of the object connection ports  13  via corresponding one of the first holes  31   a . Thus, the corresponding one of the first holes  31   a  and the second hole  31   b  are located in the groove portion  32   b  and the corresponding one of the third holes  31   c  is located in the enclosure interior space communication portion  32   a  when exhausting air from the one of the bag-shaped members  10 . In particular, the corresponding one of the first holes  31   a  is located in the protruding portion  32   d , the second hole  31   b  is located in the circular portion  32   c  and the corresponding one of the third holes  31   c  is located in the enclosure interior space communication portion  32   a  when exhausting air from the one of the bag-shaped members  10 . 
     The air is drawn from the bag-shaped member  10  by the pump  2 , and the air flows from the bag-shaped member  10  to the object connection port  13 . Then, the air flows from the object connection port  13  to the groove portion  32   b . The air flowing into the groove portion  32   b  is drawn into the pump  2  through the air discharge port  12  that is communicated to the groove portion  32   b . In other words, the air in the groove portion  32   b  is discharged by the air discharge port  12 . The air drawn into the pump  2  is supplied to the interior space  11   a  of the enclosure  1  via the air supply port  11 . Then, the air flows from the interior space  1   a  of the enclosure  1  to the external air supply and exhaust port  14  through the enclosure interior space communication portion  32   a , and the air is discharged to the outside. 
     The control of the control unit  4  when exhausting air is basically identical to the control shown in  FIG.  14   , except that the control unit  4  drives the pump  2  for exhausting air. Specifically, after stopping the motor  8   a  of the drive unit  8  to stop the rotation of the rotating part  32  in step S 25 , the control unit  4  drives the pump  2  to exhaust air from the bag-shaped member  10  in step S 26 . If the pressure detected by the pressure sensor  6  provided to the second pipe  30   b  is less than the predetermined value in step S 27 , then the control unit  4  stops the pump  2  in step S 28  and proceeds to step S 29 . 
     (Arrangement of Rotating Part in Maintained State) 
     As shown in  FIG.  23   , in the maintained state of the inflated or deflated state of the bag-shaped members  10  for which supplying air and exhausting air is stopped, the enclosure interior space communication portion  32  a is not communicated to the first holes  31   a  and the third holes  31   c . In addition, with the groove portion  32   b , the circular portion  32   c  is communicated to the second hole  31   b , but the groove portion  32   b  (the circular portion  32   c  and the protruding portion  32   d ) is not communicated to the first holes  31   a  and the third holes  31   c . Thus, the first holes  31   a  and the third holes  31   c  are blocked by the rotating part  32  when maintaining the inflated state or the deflated state of the bag-shaped members  10 . Therefore, neither a flow path between the first holes  31   a  and the second hole  31   b  nor a flow path between the second hole  31   b  and the third holes  31   c  is not formed. Thus, air is not supplied to the pump  2  either from the outside or from the bag-shaped members  10 . As a result, air is neither supplied to the bag-shaped members  10  nor discharged from the bag-shaped members  10 , and the bag-shaped members  10  can maintain the inflated state or the deflated state. 
     Other configurations of the air supply device  200  according to the second embodiment are the same as those of the air supply device  100  according to the first embodiment described above. 
     Effects of Second Embodiment 
     In the second embodiment, the following effects can be obtained. 
     In the second embodiment, as described above, the air supply device  200  comprises the enclosure  1 , the pump  2 , and the flow path switching unit  3 . The enclosure  1  has the sealed interior space  1   a  for storing air therein. The pump  2  is provided outside the enclosure  1 . The pump  2  is configured to supply air to the interior space  1   a  of the enclosure  1 . The flow path switching unit  3  includes the pedestal part  31  mounted inside the enclosure  1 , the rotating part  32  rotatably mounted on the pedestal part  31 , the rotating part  32  having the enclosure interior space communication portion  32   a  and the groove portion  32   b , and the drive unit  8  configured to rotate the rotating part  32 . The enclosure  1  includes the air supply port  11  for supplying air supplied from the pump  2  to the interior space  1   a  of the enclosure  1 , the air discharge port  12  for discharging air from the groove portion  32   b  of the rotating part  32 , and the object connection ports  13  for supplying air to or exhausting air from the bag-shaped members  10 . The pedestal part  31  includes the first holes  31   a  that are communicated to the object connection ports  13 , and the second hole  31   b  that is communicated to the air discharge port  12 . The enclosure interior space communication portion  32   a  is communicated to the air supply port  11  through the interior space  1   a  of the enclosure  1 . The groove portion  32   b  is separated from the enclosure interior space communication portion  32   a.    
     The enclosure interior space communication portion  32   a  includes a notch or a through hole that is provided on the outer portion of the rotating part  32 . The notch or the through hole opens toward the pedestal part  31  and the enclosure  1  so as to be communicated to the air supply port  11  through the interior space  1   a  of the enclosure  1 . The groove portion  32   b  opens toward the pedestal part  31  so as not to be directly communicated to the enclosure interior space communication portion  32   a.    
     With this configuration, the rotating part  32  includes the enclosure interior space communication portion  32   a  on the outer portion of the rotating part  32 . Therefore, the sealed interior space  1   a  of the enclosure  1  can be used as a flow path for supplying air or exhausting air, and thus there is no need to provide a groove for forming a flow path in an outer circumference of the rotating part  32 . With this configuration, enlargement of the flow path switching unit  3  can be suppressed. As a result, enlargement of the air supply device  200  can be suppressed. 
     In the second embodiment, as described above, the enclosure  1  includes the external air supply and exhaust ports  14  for supplying air from the outside of the enclosure  1  to the interior space  1   a  of the enclosure or exhausting air from the interior space  1   a  of the enclosure  1  to the outside of the enclosure  1 . The pedestal part  31  includes the third holes  31   c  that are communicated to the external air supply and exhaust ports  14 . 
     The air discharge port  12  is connected to the air intake port  2   a  of the pump  2 . 
     When supplying air to one of the bag-shaped members  10 , the control unit  4  is configured to control the drive unit  8  to rotate the rotating part  32  such that the enclosure interior space communication portion  32   a  forms the flow path between one of the first holes  31   a  and the air supply port  11  through the interior space  1   a  of the enclosure  1  and the groove portion  32   b  forms the flow path between the second hole  31   b  and one of the third holes  31   c . When exhausting air from the one of the bag-shaped members  10 , the control unit  4  is configured to control the drive unit  8  to rotate the rotating part  32  such that the enclosure interior space communication portion  32   a  forms the flow path between the air supply port  11  and the one of the third holes  31   c  through the interior space  1   a  of the enclosure  1  and the groove portion  32   b  forms the flow path between the one of the first holes  31   a  and the second hole  31   b . With this configuration, when supplying air to the one of the bag-shaped members  10 , air flows in the order of the one of the third holes  31   c , the second hole  31   b , the pump  2 , the air supply port  11 , the interior space  1   a  of the enclosure  1 , the one of the first holes  31   a , and the one of the bag-shaped members  10  from one of the external air supply and exhaust ports  14 . Thus, air can be supplied to the one of the bag-shaped members  10  from the outside of the enclosure  1 . Also, when exhausting air from the one of the bag-shaped members  10 , air flows in the order of the one of the first holes  31   a , the second hole  31   b , the pump  2 , the air supply port  11 , the one of the third holes  31   c , and the one of the external air supply and exhaust ports  14  from the one of the bag-shaped members  10 . Thus, air inside the one of the bag-shaped members  10  can be discharged to the outside of the enclosure. 
     In the second embodiment, as described above, the pedestal part  31  includes the first holes  31   a  and the third holes  31   c  that are provided corresponding to the bag-shaped members  10 . The control unit  4  is configured to switch the bag-shaped members  10  for supplying and exhausting air by rotating the rotating part  32  to switch the first holes  31   a  and the third holes  31   c  to be communicated to the enclosure interior space communication portion  32   a  and the groove portion  32   b . With this configuration, among the first holes  31   a  and the third holes  31   c , air flows to one of the first holes  31   a  and one of the third hole  31   c  that are communicated to the enclosure interior space communication portion  32   a  and the groove portion  32   b , while air does not flow to other first holes  31   a  and other third holes  31   c . With this configuration, it is possible to supply and exhaust air to a desired one of the bag-shaped members  10  among the bag-shaped members  10 . 
     In the second embodiment, as described above, the control unit  4  is configured to switch the bag-shaped members  10  for supplying and exhausting air by rotating the rotating part  32  at the predetermined angle or at the predetermined interval. With this configuration, switching of the bag-shaped members  10  can be easily performed by setting the predetermined angle or the predetermined interval in accordance with positions of the first holes  31   a , the second hole  31   b  and the third holes  31   c.    
     In the second embodiment, as described above, when viewed from the pedestal part  31  side, the enclosure interior space communication portion  32   a  has an elliptical shape inwardly depressed. The groove portion  32   b  has the circular portion  32   c  that is communicated to the second hole  31   b , and the protruding portion  32   d  that is selectively communicated to the first holes  31   a  and that outwardly protrudes from the circular portion  32   c . With this configuration, the outer circumferences of the enclosure interior space communication portion  32   a  and the groove portion  32   b  can be aligned with the outer circumferences of the first hole  31   a , the second hole  31   b  and the third hole  31   c  without misalignment. Thus, it is possible to prevent supplying air to the bag-shaped member  10  or exhausting air from the bag-shaped member  10  in a state in which the first hole  31   a , the second hole  31   b  and the third hole  31   c  are partially blocked by the rotating part  32 . 
     Other effects of the air supply device  200  according to the second embodiment are the same as those of the air supply device  100  according to the first embodiment described above. 
     Modification Examples 
     The embodiments disclosed here should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims, not by the description of the embodiments described above, and furthermore includes all changes (modification examples) within the meaning and scope equivalent to the claims. 
     For example, in the first and second embodiments above, examples are shown in which the external air supply and exhaust ports are provided, but the present invention is not limited to this. For example, it may be configured without an external air supply and exhaust port. 
     In the first and second embodiments, examples are shown in which air is supplied to and exhausted from a single bag-shaped member, but the present invention is not limited to this. For example, air may be simultaneously supplied to a plurality of bag-shaped members, and may be simultaneously exhausted from a plurality of bag-shaped members. In this case, the groove portion may have a plurality of protruding portions. 
     In the first and second embodiments, examples are shown in which the plurality of the bag-shaped members are provided, but the present invention is not limited to this. For example, there may be only one bag-shaped member. In this case, one first hole and one third hole are provided in the pedestal part, and one object connection port and one external air supply and exhaust ports are provided in the enclosure. 
     In the first and second embodiments, examples are shown in which the pressure sensors are arranged near the air outlet port of the pump and near the air intake port of the pump, but the present invention is not limited to this. For example, they may be provided near the air supply and exhaust ports of the bag-shaped members. 
     In the first and second embodiments, examples are shown in which the control unit rotates the rotating part by every predetermined angle, but the present invention is not limited to this. For example, the control unit may rotate the rotating part at every predetermined interval. In this case, the predetermined interval may be set, from the initial position, corresponding to the interval at which the first holes are arranged, or corresponding to the interval at which the first holes and the third holes are arranged. 
     (1) In view of the state of the known technology, an air supply device according to an aspect of this disclosure comprises an enclosure, a pump, and a flow path switching unit. The enclosure has a sealed interior space for storing air therein. The pump is provided outside the enclosure. The pump is configured to supply air to the interior space of the enclosure. The flow path switching unit including a pedestal part mounted inside the enclosure, a rotating part rotatably mounted on the pedestal part, the rotating part having an enclosure interior space communication portion and a groove portion, and a drive unit configured to rotate the rotating part. The enclosure includes an air supply port for supplying air from the pump to the interior space of the enclosure, an air discharge port for discharging air from the groove portion of the rotating part, and at least one object connection port for supplying air to or exhausting air from at least one object. The pedestal part includes at least one first hole that is communicated to the at least one object connection port, and a second hole that is communicated to the air discharge port. The enclosure interior space communication portion is communicated to the air supply port through the interior space of the enclosure. The groove portion is separated from the enclosure interior space communication portion. 
     (2) In accordance with a preferred embodiment according to the air supply device mentioned above, the enclosure interior space communication portion includes a notch or a through hole that is provided on an outer portion of the rotating part. The notch or the through hole opens toward the pedestal part and the enclosure so as to be communicated to the air supply port through the interior space of the enclosure. The groove portion is provided on an inner portion of the rotating part. The groove portion opens toward the pedestal part so as not to be directly communicated to the enclosure interior space communication portion. 
     The air supply device according to the aspect of this disclosure, as mentioned above, comprises the flow path switching unit including the pedestal part mounted inside the enclosure, the rotating part rotatably mounted on the pedestal part, the rotating part having the enclosure interior space communication portion and the groove portion, and the drive unit configured to rotate the rotating part. The enclosure interior space communication portion includes the notch or the through hole that is provided on the outer portion of the rotating part, the notch or the through hole opening toward the pedestal part and the enclosure so as to be communicated to the air supply port through the interior space of the enclosure, for example. The groove portion is provided on the inner portion of the rotating part, the groove portion opening toward the pedestal part so as not to be directly communicated to the enclosure interior space communication portion, for example. With this configuration, the rotating part includes the enclosure interior space communication portion on the outer portion of the rotating part. Therefore, the sealed interior space of the enclosure can be used as a flow path for supplying air or exhausting air, and thus there is no need to provide a groove for forming a flow path in an outer circumference of the rotating part. With this configuration, enlargement of the flow path switching unit can be suppressed. As a result, enlargement of the air supply device can be suppressed. 
     (3) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, when viewed from the pedestal part side, the enclosure interior space communication portion has an elliptical shape inwardly depressed. The groove portion has a circular portion that is communicated to the second hole, and a protruding portion that is selectively communicated to the at least one first hole and that outwardly protrudes from the circular portion. With this configuration, outer circumferences of the enclosure interior space communication portion and the groove portion can be aligned with outer circumferences of the at least one first hole and the second hole without misalignment. Thus, it is possible to prevent supplying air to the at least one object or exhausting air from the at least one object in a state in which the at least one first hole and the second hole are partially blocked by the rotating part. 
     (4) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, one of the at least one first hole is located in the enclosure interior space communication portion when supplying air to one of the at least one object, and the one of the at least one first hole and the second hole are located in the groove portion when exhausting air from the one of the at least one object. 
     (5) In accordance with a preferred embodiment according to the air supply device mentioned above, the air supply device further comprises a control unit configured to control the drive unit to rotate the rotating part to a position at which a position of one of the at least one first hole and a position of the enclosure interior space communication portion coincide to each other when supplying air to one of the at least one object, and the control unit being configured to control the drive unit to rotate the rotating part to a position at which the one of the at least one first hole and the second hole are communicated to each other through the groove portion when exhausting air from the one of the at least one object. With this configuration, when supplying air to the one of the at least one object, the enclosure interior space communication portion and the one of the at least one first hole are communicated to each other and a flow path is formed from the interior space of the enclosure to the one of the at least one object. Thus, air inside the enclosure can be supplied to the one of the at least one object. Also, when exhausting air from the one of the at least one object, the one of the at least one first hole and the second hole are communicated to each other and a flow path is formed from the one of the at least one object to the air discharge port. Thus, the air can be exhausted from the one of the at least one object. 
     (6) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the control unit is configured to switch the at least one object for supplying and exhausting air by rotating the rotating part at a predetermined angle or at a predetermined interval. With this configuration, switching of the at least one object can be easily performed by setting the predetermined angle or the predetermined interval in accordance with positions of the at least one first hole and the second hole. 
     (7) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the air supply device further comprises a pressure sensor for measuring a pressure of air supplied to the interior space of the enclosure or exhausted from the interior space of the enclosure. When supplying air to the one of the at least one object, the control unit is configured to control the drive unit to rotate the rotating part to a position at which no flow path is formed between the at least one first hole and the second hole while the pressure detected by the pressure sensor is higher than or equal to a predetermined value. With this configuration, the control unit can acquire that air has been sufficiently supplied to the one of the at least one object based on the fact that air pressure in the one of the at least one object in a full air state has become more than or equal to the predetermined value. In addition, when the pressure detected by the pressure sensor is more than or equal to the predetermined value, no flow path is formed between the at least one first hole and the second hole. Thus, no flow path is formed from the one of the at least one object to the air discharge port, and it is possible to prevent that air is discharged from the one of the at least one object. 
     (8) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, when exhausting air from the one of the at least one object, the control unit is configured to control the drive unit to rotate the rotating part to a position at which no flow path is formed between the at least one first hole and the second hole while the pressure detected by the pressure sensor is less than a predetermined value. With this configuration, by setting the predetermined value to an air pressure in the one of the at least one object in a sufficiently exhausted state, it is possible for the control unit to acquire that air has been sufficiently exhausted from the one of the at least one object. Also, no flow path is formed between the at least one first hole and the second hole while the pressure is less than the predetermined value. Thus, no flow path is formed from the one of the at least one object to the air discharge port, and it is possible to prevent that air is excessively discharged from the object. 
     (9) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the control unit is configured to stop a drive of the pump when rotating the rotating part. With this configuration, for example, when supplying air to one object by communicating one of a plurality of first holes to the enclosure interior space communication portion, it is possible to prevent that air supplied to the interior space of the enclosure is supplied by the pump to other object by communicating other first hole to the enclosure interior space communication portion during rotation of the rotating part. 
     (10) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the rotating part includes a gear portion formed on an outer circumferential surface of the rotating part, and the control unit is configured to control the drive unit to rotate the rotating part in a state in which the drive unit and the gear portion are engaged. With this configuration, the rotating part can function as a reduction gear by varying the number of teeth between the drive unit and the gear portion. 
     (11) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the enclosure includes at least one external air supply and exhaust port for supplying air from an outside of the enclosure to the interior space of the enclosure or exhausting air from the interior space of the enclosure to the outside of the enclosure. The pedestal part includes at least one third hole that is communicated to the at least one external air supply and exhaust port. 
     (12) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, one of the at least one first hole is located in the enclosure interior space communication portion and the second hole and one of the at least one third hole are located in the groove portion when supplying air to one of the at least one object. The one of the at least one first hole and the second hole are located in the groove portion and the one of the at least one third hole is located in the enclosure interior space communication portion when exhausting air from the one of the at least one object. 
     (13) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the air discharge port is connected to an air intake port of the pump. 
     (14) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, when supplying air to the one of the at least one object, the control unit is configured to control the drive unit to rotate the rotating part such that the enclosure interior space communication portion forms a flow path between one of the at least one first hole and the air supply port through the interior space of the enclosure and the groove portion forms a flow path between the second hole and one of the at least one third hole. When exhausting air from the one of the at least one object, the control unit is configured to control the drive unit to rotate the rotating part such that the enclosure interior space communication portion forms a flow path between the air supply port and the one of the at least one third hole through the interior space of the enclosure and the groove portion forms a flow path between the one of the at least one first hole and the second hole. With this configuration, when supplying air to the one of the at least one object, air flows in the order of the one of the at least one third hole, the second hole, the pump, the air supply port, the interior space of the enclosure, the one of the at least one first hole and the one of the at least one object from the external air supply and exhaust port. Thus, air can be supplied to the one of the at least one object from the outside of the enclosure. Also, when exhausting air from the one of the at least one object, air flows in the order of the one of the at least one first hole, the second hole, the pump, the air supply port, the one of the at least one third hole and the external air supply and exhaust port from the one of the at least one object. Thus, air inside the one of the at least one object can be discharged to the outside of the enclosure. 
     (15) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the at least one first hole and the at least one third hole include a plurality of first holes and a plurality of third holes that are provided corresponding to a plurality of objects. The control unit is configured to switch the objects for supplying and exhausting air by rotating the rotating part to switch the first holes and the third holes to be communicated to the enclosure interior space communication portion and the groove portion. With this configuration, among the plurality of the first holes and the plurality of the third holes, air flows to a first hole and a third hole that are communicated to the enclosure interior space communication portion and the groove portion, while air does not flow to other first holes and other third holes. With this configuration, it is possible to supply and exhaust air to a desired object among the plurality of objects. 
     (16) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the groove portion has a circular portion and a protruding portion that is communicated to the circular portion and outwardly protrudes from the circular portion. One of the at least one first hole is located in the enclosure interior space communication portion and the second hole is located in the circular portion when supplying air to one of the at least one object. The one of the at least one first hole is located in the protruding portion and the second hole is located in the circular portion when exhausting air from the one of the at least one object. 
     (17) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the one of the at least one first hole is blocked by the rotating part when maintaining an inflated state or a deflated state of the one of the at least one object. 
     (18) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the groove portion has a circular portion and a protruding portion that is communicated to the circular portion and outwardly protrudes from the circular portion. One of the at least one first hole is located in the enclosure interior space communication portion, the second hole is located in the circular portion and one of the at least one third hole is located in the protruding portion when supplying air to one of the at least one object. The one of the at least one first hole is located in the protruding portion, the second hole is located in the circular portion and the one of the at least one third hole is located in the enclosure interior space communication portion when exhausting air from the one of the at least one object. 
     (19) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the one of the at least one first hole and the one of the at least one third hole are blocked by the rotating part when maintaining an inflated state or a deflated state of the one of the at least one object. 
     (20) In accordance with a preferred embodiment according to any one of the air supply devices mentioned above, the groove portion has a circular portion and a protruding portion that is communicated to the circular portion and outwardly protrudes from the circular portion, the protruding portion being located opposite to the enclosure interior space communication portion with respect to a rotational center of the rotating part. 
     According to the present disclosure, it is possible to provide an air supply device capable of suppressing enlargement of the flow path switching unit. 
     In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section,” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts unless otherwise stated. 
     As used herein, the following directional terms “forward”, “rearward”, “front”, “rear”, “up”, “down”, “above”, “below”, “upward”, “downward”, “top”, “bottom”, “side”, “vertical”, “horizontal”, “perpendicular” and “transverse” as well as any other similar directional terms refer to those directions of an air supply device in an upright position on a horizontal surface. Accordingly, these directional terms, as utilized to describe the air supply device should be interpreted relative to an air supply device in an upright position on a horizontal surface. 
     The phrase “at least one of” as used in this disclosure means “one or more” of a desired choice. For one example, the phrase “at least one of” as used in this disclosure means “only one single choice” or “both of two choices” if the number of its choices is two. For another example, the phrase “at least one of” as used in this disclosure means “only one single choice” or “any combination of equal to or more than two choices” if the number of its choices is equal to or more than three. Also, the term “and/or” as used in this disclosure means “either one or both of”. 
     The term “attached” or “attaching”, as used herein, encompasses configurations in which an element is directly secured to another element by affixing the element directly to the other element; configurations in which the element is indirectly secured to the other element by affixing the element to the intermediate member(s) which in turn are affixed to the other element; and configurations in which one element is integral with another element, i.e. one element is essentially part of the other element. This definition also applies to words of similar meaning, for example, “joined”, “connected”, “coupled”, “mounted”, “bonded”, “fixed” and their derivatives. Finally, terms of degree such as “substantially”, “about” and “approximately” as used herein mean an amount of deviation of the modified term such that the end result is not significantly changed. 
     While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, unless specifically stated otherwise, the size, shape, location or orientation of the various components can be changed as needed and/or desired so long as the changes do not substantially affect their intended function. Unless specifically stated otherwise, components that are shown directly connected or contacting each other can have intermediate structures disposed between them so long as the changes do not substantially affect their intended function. The functions of one element can be performed by two, and vice versa unless specifically stated otherwise. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such feature(s). Thus, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.