Abstract:
A massage apparatus includes: a pump that is an air supply source; a motor that actuates a distributor; a power switch that optionally supplies power to the pump and the motor to actuate the pump and the motor; and a limit switch that is connected in parallel with the power switch, and is operated by a cam working with the distributor so as to be turned ON when the distributor assumes a position to supply air to any of bladders, and so as to be turned OFF when the distributor assumes a position to discharge air from at least any of the bladders.

Description:
INCORPORATION BY REFERENCE 
       [0001]    The disclosure of Japanese Patent Application No. 2014-212299 filed on Oct. 17, 2014 including the specification, drawings and abstract is incorporated herein by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates to a massage apparatus that performs a desired massage by supplying and discharging air to and from a bladder provided in the apparatus of a seat or the like. 
         [0004]    2. Description of Related Art 
         [0005]    In an air mat apparatus disclosed in Japanese Patent Application Publication No. 9-38153, a plurality of bladders are arranged in a planar manner to constitute an air mat. The bladders are divided into a plurality of groups, and air is alternately supplied to and discharged from the bladders in the respective groups, so that a body of a person lying on the air mat is massaged. 
         [0006]    With similar uses as the above air mat apparatus, a massage seat for a vehicle is developed. The massage seat has a plurality of bladders arranged inside a vehicle seat. The bladders are divided into a plurality of groups, and air is alternately supplied to and discharged from the bladders in the respective groups, so that a body of a seated occupant is massaged. During a massage operation being actuated, air is alternately supplied to and discharged from the bladders in the respective groups disposed in the respective part of the vehicle seat via a distributer. When the massage operation is stopped, air is discharged from the bladders so that the bladders become the initial state. It is because no part of the vehicle seat is deformed due to the inflated bladders when the massage operation is stopped so that the massage seat is used as a regular vehicle seat. Accordingly, the distributor is provided with a rotational position detection sensor so that an air discharge position of the distributor is detected. When the air discharge position of the distributor is detected by the rotational position detection sensor, each of the operations of the distributor and a pump as an air supply source is stopped. That is, the distributor and the pump continue to be actuated even after the massage operation of the massage seat is stopped until the air discharge position of the distributor is detected. When the air discharge position of the distributor is detected, the actuations of the distributor and the pump are automatically stopped. 
         [0007]    However, in the above conventional massage seat, an optical sensor is used as the rotational position detection sensor, and the air discharge position of the distributor is specified by using a counter. Thus, a circuit that actuates the counter upon receiving a signal from the optical sensor is required, so that a configuration becomes disadvantageously complicated, and a cost is disadvantageously increased. 
       SUMMARY OF THE INVENTION 
       [0008]    The invention provides a massage apparatus that performs a massage action by sequentially supplying and discharging air to and from a plurality of bladders via a distributor, and stops the massage action after continuing the action until the distributor assumes an air discharge position at the time of stopping the massage action, wherein a configuration of an electric circuit that actuates a pump and the distributor is simplified by directly stopping the pump and the distributor by a cam switch that is actuated upon receiving a motion of the distributor. 
         [0009]    An aspect of the invention is a massage apparatus that performs a massage action by sequentially supplying and discharging air to and from a plurality of bladders via a distributor, the massage apparatus including: a pump that is an air supply source; a motor that actuates the distributor; a power switch that optionally supplies power to the pump and the motor to actuate the pump and the motor; and a limit switch that is connected in parallel with the power switch, and is operated by a cam working with the distributor so as to be turned ON when the distributor assumes a position to supply air to any of the bladders, and so as to be turned OFF when the distributor assumes a position to discharge air from at least any of the bladders. 
         [0010]    According to the aspect of the invention, the pump and the distributor are actuated when the power switch is turned ON, so that the air supply and the air discharge with respect to the bladders are performed. When the power switch is turned OFF, the power supply to the pump and the distributor is continued via the limit switch, and the pump and the distributor are continuously actuated until the distributor assumes the air discharge position. When the distributor reaches the air discharge position, the limit switch is turned OFF by the cam working with the distributor, so that the actuation of the pump and the distributor is stopped. Therefore, the pump and the distributor are always stopped at the air discharge position of the distributor. Moreover, since the pump and the distributor are stopped by the cam working with the distributor and the limit switch, an extra circuit such as a conventional circuit that actuates a counter becomes unnecessary, and a circuit configuration can be simplified. 
         [0011]    In the aspect of the invention, the distributor may be a rotary-type distributor, and the rotary-type distributor may include: a stator having a plurality of output ports that are air passages connected to the bladders, respectively, an air supply port that is an air passage connected to the pump, and an air discharge port that is an air passage open to an atmosphere; a rotor that rotates relative to the stator, and, at each of a plurality of air supply positions set for each predetermined rotational angle, brings the air supply port into communication with an output port of a bladder corresponding to the air supply position out of the output ports, and, at a plurality of air discharge positions set between the respective air supply positions, brings the air discharge port into communication with the output port most recently in communication with the air supply port; and the cam that is set on a rotational outer periphery of the rotor, and is formed so as to turn OFF the limit switch at a position corresponding to each of the air discharge positions, and turn ON the limit switch at a position other than the air discharge positions. 
         [0012]    According to the above structure, the cam has such a structure as to turn OFF the limit switch at each of the air discharge positions during the rotation of the rotor. Thus, the cam can be configured only by forming such a cam shape as to turn OFF the limit switch according to each of the air discharge positions for the predetermined rotational angles of the rotor on the rotational outer periphery of the rotor, and the cam structure can be simplified. 
         [0013]    In aspect of the invention, in the stator, the plurality of output ports may be dispersedly arranged in a circular shape, the air supply port may be disposed in the center of the circular shape, the air discharge port may be disposed between the output ports and the air supply port in a radial direction of the circular shape, the plurality of air discharge ports may be dispersedly arranged concentrically with the plurality of output ports, and the rotor may bring the output port most recently in communication with the air supply port into communication with all of the air discharge ports at each of the air discharge positions. 
         [0014]    According to the above structure, the output port is brought into communication with the plurality of air discharge ports at each of the air discharge positions. Thus, an air discharge capacity can be increased, and an air discharge rate of each of the bladders can be raised. Also, even when the air discharge capacity is increased, an amount of air discharged from each of the air discharge ports is not increased. Thus, a discharge sound generated when air flows through the air discharge ports at high speed can be suppressed. 
         [0015]    In the aspect of the invention, the cam may include a projection that is provided projecting to an outer peripheral side of the rotor corresponding to each of the air discharge positions set between the respective air supply positions in the rotor, the limit switch may be turned OFF when the projection of the cam comes into abutment with the limit switch, and may be turned ON when the projection of the cam is separated from the limit switch, and the projection may be formed so as to have an inclined surface at a front end portion in a rotational direction of the rotor such that a projection amount with respect to the limit switch is gradually increased along with the rotation of the rotor when the projection starts to abut with the limit switch. 
         [0016]    According to the above structure, the projection of the cam is formed so as to have the inclined surface at the front end portion. As a result, an abutting force generated when the projection and the limit switch come into abutment with each other is not rapidly increased, but is gradually increased. Accordingly, wear of an abutting portion between the projection and the limit switch is suppressed, and durability can be improved. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    Features, advantages, and technical and industrial significance of exemplary embodiments of the invention will be described below with reference to the accompanying drawings, in which like numerals denote like elements, and wherein: 
           [0018]      FIG. 1  is a perspective view illustrating a state in which a massage apparatus according to one embodiment of the invention is mounted in an automobile seat; 
           [0019]      FIG. 2  is a system configuration diagram illustrating electrical wiring and air piping in the above embodiment; 
           [0020]      FIG. 3  is a front view illustrating an appearance of a rotary-type distributor in the above embodiment; 
           [0021]      FIG. 4  is a side view illustrating the appearance of the rotary-type distributor similarly to  FIG. 3 ; 
           [0022]      FIG. 5  is a plan view illustrating the appearance of the rotary-type distributor similarly to  FIG. 3 ; 
           [0023]      FIG. 6  is a bottom view illustrating the appearance of the rotary-type distributor similarly to  FIG. 3 ; 
           [0024]      FIG. 7  is a plan view of a stator of the rotary-type distributor in the above embodiment; 
           [0025]      FIG. 8  is a sectional view taken along a line VIII-VIII in  FIG. 7 ; 
           [0026]      FIG. 9  is an enlarged bottom view of a rotor of the rotary-type distributor in the above embodiment; 
           [0027]      FIG. 10  is a sectional view taken along a line X-X in  FIG. 9 ; 
           [0028]      FIG. 11  is a sectional view illustrating a state when the rotor is at an air supply position for explaining a function of the rotary-type distributor in the above embodiment; and 
           [0029]      FIG. 12  is a sectional view illustrating a state when the rotor is at an air discharge position similarly to  FIG. 11 . 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0030]      FIGS. 1 to 12  show one embodiment of the invention. The embodiment shows an example in which a massage apparatus according to the invention is applied to an vehicle seat (hereinafter referred to simply as a seat). The massage apparatus includes a plurality of bladders  311  to  316 ,  321  to  324  that are disposed along a seating surface of a seatback  2  constituting a backrest and a seating surface of a seat cushion  1  constituting a seat portion in the seat, respectively. A headrest  3  that supports a head portion of an occupant from behind is also provided on an upper portion of the seatback  2 . 
         [0031]    Here, the bladders  321  to  324  on the seat cushion 1-side are bilaterally paired into two pairs, and the two pairs are respectively arranged on a front side and a rear side of the seat. The bladders  311  to  316  on the seatback 2-side are bilaterally paired into three pairs, and the three pairs are vertically arranged. The bladders  311  to  316  are fixed onto a bladder base  301  that is fixed within the seatback  2 , and the bladders  321  to  324  are fixed onto a bladder base  301  that is fixed within the seat cushion  1 . Each of hoses  330  is connected to each of the bladders  311  to  316 ,  321  to  324 , and air is supplied thereto from a pump  400  via a rotary valve  230  described below. The bladders  311  to  316 ,  321  to  324  are configured to sequentially inflate with air supplied therein, and press the surfaces of the seat cushion  1  and the seatback  2  from inside. When air in the bladders  311  to  316 ,  321  to  324  is sequentially discharged, the bladders  311  to  316 ,  321  to  324  deflate, and a force for pressing the surfaces of the seat cushion  1  and the seatback  2  is released. Thus, the seat cushion  1  and the seatback  2  are restored to a normal state. 
         [0032]    Air is supplied to and discharged from each of the bilateral pairs of the bladders  311  to  316 ,  321  to  324  as one set. For example, air is sequentially supplied to and discharged from the bladders  311  to  316 ,  321  to  324  from the rear side to the front side in the seat cushion  1  and from a lower side to an upper side in the seatback  2 , so that a body of an occupant is massaged. Of course, air may be supplied to and discharged from the bladders  311  to  316 ,  321  to  324  in a reversed order from that described above. 
         [0033]      FIG. 2  shows electrical wiring and air piping used for performing the air supply and the air discharge with respect to the respective bladders  311  to  316 ,  321  to  324 . The respective bladders  311  to  316 ,  321  to  324  are configured to be supplied with compressed air generated by the pump  400  via the rotary valve  230 . The rotary valve  230  is configured to sequentially distribute air to the bladders  311  to  316 ,  321  to  324  as described above with a rotor  232  described below being rotated by a motor  210  via a gear in a gearbox  220 . 
         [0034]    The pump  400  includes two pumps  410 ,  420  that are arranged in parallel with each other. Motors of the two pumps  410 ,  420  are also electrically connected in parallel with each other, and are connected to a power source (not shown) via a relay  120 . The above motor  210  is also connected in parallel with the two pumps  410 ,  420 . The relay  120  is connected to a refresh switch  110  so as to be put into an ON state according to an operation of the refresh switch  110 . The refresh switch  110  includes a timer  111 . When a switch (not shown) provided in the refresh switch  110  is operated by one-touch, a contact of the relay  120  is put into an ON state by a period of time previously set by using a function of the timer  111 . 
         [0035]    Therefore, when the switch of the refresh switch  110  is operated by one-touch, the two pumps  410 ,  420 , and the motor  210  are actuated by the set period of time, and air is sequentially supplied to and discharged from the bladders  311  to  316 ,  321  to  324 . Projections  236  that constitute a cam are provided on an outer peripheral surface of the rotor  232  of the rotary valve  230 . The number of the projections  236  is five that is equal to the number of sets of the bladders  311  to  316 ,  321  to  324 . A limit switch  240  that is operated by the respective projections  236  to be turned OFF is provided. Each of the projections  236  is configured to turn OFF the limit switch  240  when the rotor  232  is at an air discharge position. The limit switch  240  is connected in parallel with the contact of the relay  120 . When the contact of the relay  120  is changed from the ON state to an OFF state, the limit switch  240  remains to be turned ON until the rotor  232  reaches the air discharge position. Thus, the two pumps  410 ,  420 , and the motor  210  are continuously actuated. When the rotor  232  reaches the air discharge position, and the limit switch  240  is turned OFF, the actuation of the two pumps  410 ,  420 , and the motor  210  is stopped. When the respective bladders  311  to  316 ,  321  to  324  are stopped after performing a massage action by the set period of time as described above, the respective bladders  311  to  316 ,  321  to  324  are in a discharged state. The seat is thereby prevented from being in a deformed state by bladders  300  after the massage action is finished. Although the bladders  300  are actuated only by the period of time set by the timer  111 , the bladders  300  may be continuously actuated while the switch is being operated. 
         [0036]      FIGS. 3 to 6  show an appearance of a rotary-type distributor  200 . The rotary-type distributor  200  employs a stator  231  of the rotary valve  230  as a base member, and the gearbox  220  and the motor  210  are attached to the stator  231 . To be more specific, a motor base  250  is supported by three posts  260  on the stator  231 , and the motor  210  is attached onto the motor base  250  via a motor attachment plate  211 . The gearbox  220  is also supported below the motor base  250 . As described below, the rotor  232  of the rotary valve  230  disposed below the gearbox  220  is configured to be rotated by an output shaft of the gearbox  220 . Moreover, the limit switch  240  that is operated by the projections  236  of the cam on an outer periphery of the rotor  232  of the rotary valve  230  is supported on the stator  231 . 
         [0037]      FIGS. 7, 8  show the stator  231  alone. A recessed portion  231   a  that receives the rotor  232  is formed in a surface of the stator  231 . Five output holes  234   a  that are air passages connected to the bladders  311  to  316 ,  321  to  324 , respectively, one air supply hole  233   a  that is an air passage connected to the pumps  410 ,  420 , and five air discharge holes  235   a  that are air passages open to the atmosphere are formed in a bottom of the recessed portion  231   a.  The output holes  234   a  are dispersedly arranged in a circular shape, and the air supply hole  233   a  is disposed in the center of the circular shape. The air discharge holes  235   a  are disposed between the output holes  234   a  and the air supply hole  233   a  in a radial direction of the circular shape, and are dispersedly arranged concentrically with the output holes  234   a.    
         [0038]      FIGS. 9, 10  show the rotor  232  alone. The rotor  232  is rotated within the recessed portion  231   a  of the stator  231  with a bottom surface being fitted to the recessed portion  231   a.  A connection portion  232   f  is formed projecting on an upper surface of the rotor  232 , and is connected to the output shaft of the gearbox  220  such that the rotor  232  is rotated upon receiving a rotational output of the output shaft. A tower portion  232   e  is provided corresponding to the air supply hole  233   a  of the stator  231  on the bottom surface of the rotor  232 . An output groove  232   a  is provided corresponding to a portion of the circular shape in which the output holes  234   a  of the stator  231  are disposed, and an air discharge groove  232   b  is provided corresponding to both of a remaining portion of the circular shape in which the output holes  234   a  of the stator  231  are disposed and an entire circular shape in which the air discharge holes  235   a  are disposed. Therefore, the air discharge groove  232   b  is formed so as to circumferentially sandwich the output groove  232   a.  The output groove  232   a  is set to an angular range A that does not include more than one output hole  234   a  of the stator  231  at the same time. The air discharge groove  232   b  is set to an angular range B that includes four of the output holes  234   a  of the stator  231 , but not five, at the same time. All of the five air discharge holes  235   a  correspond to the air discharge groove  232   b  at all times regardless of a rotational angle of the rotor  232 . 
         [0039]    An air supply passage  232   c  is formed through the tower portion  232   e.  The air supply passage  232   c  is in communication with the output groove  232   a  in the rotor  232 . The air supply passage  232   c  is formed opening in a side portion of the rotor  232  for convenience of manufacture. A steel ball  232   d  is press-fitted into an end portion of the air supply passage  232   c  in order to close the opening. 
         [0040]    An outer circumference of the rotor  232  has a cam shape. Each of the projections  236  of the cam is formed projecting at an angular position where each of the output holes  234   a  of the stator  231  most recently corresponding to the output groove  232   a  of the rotor  232  assumes a position corresponding to the air discharge groove  232   b  of the rotor  232  with the rotor  232  moving to the air discharge position. As described above, each of the projections  236  comes into abutment with the limit switch  240  to turn OFF the limit switch  240 . Each of the projections  236  is formed in a shape in which a front end portion and a rear end portion in a rotational direction of the rotor  232  have inclined surfaces, respectively, such that a projection amount with respect to the limit switch  240  gradually changes along with the rotation of the rotor  232  at a start and an end of the abutment with the limit switch  240 . Therefore, an abutting force at the start and the end of the abutment between each of the projections  236  and the limit switch  240  does not rapidly change, but gradually changes. Accordingly, wear of an abutting portion between each of the projections  236  and the limit switch  240  is suppressed, and durability can be improved. Since the cam is configured only by forming the projections  236  on the outer circumference of the rotor  232 , and it is not necessary to configure a new cam, a configuration can be simplified. 
         [0041]      FIGS. 11, 12  show a state in which the stator  231  and the rotor  232  of the rotary valve  230  are combined together in an enlarged manner. In  FIG. 11 , a manner in which the output groove  232   a  of the rotor  232  is at a position corresponding to one of the output holes  234   a  of the stator  231 , and air supplied to the air supply hole  233   a  is supplied to the output hole  234   a  through the air supply passage  232   c  is indicated by arrows. Joints  233   b,    234   b  are screwed into the air supply hole  233   a  and the output holes  234   a  to constitute an air supply port  233  and output ports  234 , respectively. A hose  430  from the pumps  410 ,  420  is connected to a free end of the joint  233   b  of the air supply port  233 . The hoses  330  to the bladders  311  to  316 ,  321  to  324 , respectively, are connected to free ends of the joints  234   b  of the output ports  234 . Note that the tower portion  232   e  of the rotor  232  is inserted into the air supply hole  233   a,  and forms the center of rotation of the rotor  232  in the recessed portion  231   a  of the stator  231 . A seal member that prevents air leakage between the stator  231  and the rotor  232  is provided at an appropriate position in a sliding portion between the stator  231  and the rotor  232 . 
         [0042]    In  FIG. 12 , a manner in which the output hole  234   a  most recently corresponding to the output groove  232   a  of the rotor  232  out of the output holes  234   a  of the stator  231  assumes a position corresponding to the air discharge groove  232   b  of the rotor  232 , the output hole  234   a  comes into communication with the air discharge holes  235   a  via the air discharge groove  232   b,  and the air discharge is performed is indicated by arrows. Joints  235   b  are screwed into the air discharge holes  235   a  to constitute air discharge ports  235 . Hoses may be connected to free ends of the joints  235   b  of the air discharge ports  235 , and guided to an appropriate position in a vehicle to discharge air. Alternatively, air may be directly discharged from the joints  235   b  without connecting the hoses to the joints  235   b.  At this time, all of the five air discharge holes  235   a  of the stator  231  are at positions corresponding to the air discharge groove  232   b  of the rotor  232 , so that air discharged from the bladders  300  through the output ports  234  is efficiently and quickly discharged. Moreover, since an amount of discharged air per one air discharge port  235  is reduced, a discharge sound generated when air flows through the air discharge ports  235  at high speed can be suppressed. Also, since the air discharge groove  232   b  of the rotor  232  is set to the angular range B that occupies about two thirds of the entire rotational angle of the rotor  232 , each of the output holes  234   a  continuously assumes the position corresponding to the air discharge groove  232   b  over a relatively long time after reaching the position corresponding to the air discharge groove  232   b.  Thus, the air discharge of the bladders  300  can be performed slowly over time, and a discharge sound generated when air flows through the output ports  234  at high speed can be also suppressed. 
         [0043]    In accordance with the above embodiment, since the pump  400  and the rotary-type distributor  200  are stopped by the rotor  232  (the cam) and the limit switch  240  in the rotary-type distributor  200 , an extra circuit such as a conventional circuit that actuates a counter becomes unnecessary, and a circuit configuration can be simplified. 
         [0044]    Although the particular embodiment has been described above, the invention is not limited to the appearance and the configuration, and various changes, additions, and deletions may be made therein without departing from the scope of the invention. For example, although the invention is applied to the vehicle (automobile) seat in the above embodiment, the invention may be applied to a seat mounted in aircrafts, ships, and trains. The invention may be also applied to a fixed-type exclusive massage apparatus.