Abstract:
A spine massager is disclosed to include a master air bladder, two supplementary air bladders bilaterally provided at the top side of the master air bladder, and a pressure control unit formed of a switch pressure switch and a second pressure switch and connectable to an external air pump for inflating the air bladders in such a manger that the two supplementary air bladders are alternatively inflated and exhausted after the master air bladder has been inflated to the saturated status.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a massager and more particularly, to a spine massager, which comprises a master air bladder, two supplementary air bladders bilaterally provided at the top side of the master air bladder, and pressure switch means adapted to inflate and exhaust the two supplementary air bladders alternatively after having inflated the master air bladder to the saturated status. 
   2. Description of the Related Art 
   Conventional massaging apparatus commonly use rollers for massaging the joints of the spine. When electrically connected, the rollers are rotated and moved over a part of the user&#39;s back to massage the joints of the spine. These massaging apparatus cannot stretch the user&#39;s spine to achieve a satisfactory spine massaging effect. 
   U.S. Pat. No. 6,202,237, entitled “BED HAVING MASSAGE DEVICE”, provides a bed having a number of holes for receiving a number of pneumatic actuating devices, such as the air bag type or the bellows type pneumatic actuating devices. An air pump supplies a pressurized air to the pneumatic actuating devices via a number of air valves to actuate the pneumatic actuating devices to act on the users. This design cannot lift or stretch the user&#39;s spine. 
   U.S. Pat. No. 5,848,982, entitled “LOUNGER-TYPE AIR MASSAGER”, provides a massaging device, which comprises a lounger body including a seat portion and a backrest portion provided on the rear end of the seat portion, bags provided in the seat portion and the backrest portion and adapted to inflate and deflate when compressed air is fed thereinto and discharged therefrom, and a compressed air control device for controlling the feed and discharge of the compressed air into and from the bags. The bag in the seat portion is fixed at its rear edge portion on the backrest side to the seat portion, and the bag in the backrest portion is fixed at its upper end portion to the backrest portion. The compressed air control device changes the charging time or exhaust time for the compressed air, the capacity of each bag, or the flow resistance of a charging/exhaust pipe for each bag so as to make the bag among the bags, which is subjected to a heavier load from the body weight of a person seated on the lounger body than the other bag, has the same inflation as the inflation of the other bag after the feed of the compressed air into those bags is finished. This design of massaging device does not,stretch the user&#39;s spine by lifting it. 
   U.S. Pat. No. 5,792,082, entitled “A CHAIR-TYPE AIR MASSAGER DEVICE”, provides an air massage device which has inflatable and deflatable air bags for massaging a user&#39;s body part by air pressure causing an expansion and contraction of the air bags. The air bags of this design of massage device includes air bags for a neck massage, air bags for a back massage and air bags for a waist massage, air bags for a buttocks massage, and air bags-for a thigh massage. However, because this design is a chair-type, it does not lift the user&#39;s spine to give a stretch. 
   U.S. Pat. No. 5,170,522, entitled “AIR ADJUSTABLE BED”, provides an adjustable bed, which has a foundation for supporting an air mattress. The foundation has a plurality of pivotally connected transverse plates that are moved to bend the mattress to a desired contour and shape. Open top recesses in the foundation located below the plates accommodate bags have flexible walls. The bags are separately expandable and contractible to move the plates to selected elevated positions. The recesses hold the bags in lifting positions relative to the plates when the bags are inflated. The bags fit into the recesses when deflated to allow the plates to move to a horizontal position. The bed is equipped with a vibrator that is operable to vibrate the air mattress. This design simply works to lift the user&#39;s head and/or legs. It does not lift the user&#39;s spine to give a stretch. 
   SUMMARY OF THE INVENTION 
   The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a spine massager, which massages the joints of the user&#39;s spine by means of alternatively inflating and exhausting air bladders to stretch different portions of the spine. To achieve this and other objects of the present invention, the spine massager comprises a master air bladder, the master air bladder having a top side, an air chamber defined under the top side, and a valve hole for guiding in air to inflate the air chamber of the master air bladder; a first supplementary air bladder provided at the top side of the master air bladder, the first supplementary air bladder having an air chamber and a valve hole for guiding in air to inflate the air chamber of the first supplementary air bladder; a second supplementary air bladder provided at the top side of the master air bladder and at one lateral side of the first supplementary air bladder, the second supplementary air bladder having an air chamber and a valve hole for guiding in air to inflate the air chamber of the second supplementary air bladder; and a pressure control means connected to the valve hole of the master air bladder and the valve hole of the first supplementary air bladder and the valve hole of the second supplementary air bladder and connectable to an external air pump for guiding in compressed air to the master air bladder and the first supplementary air bladder and the second supplementary air bladder and adapted to alternatively inflate and exhaust the first supplementary air bladder and the second supplementary air bladder after the master air bladder has been inflated to a saturated status, the pressure control means comprising a first pressure switch means and a second pressure switch means, the first pressure switch means comprising a first switching port connected to the valve hole of the master air bladder, a second switching port connected to the second pressure switch means, and a third switching port connectable to an external air pump, the second pressure switch means comprising a first switching port connected to the valve hole of the first supplementary air bladder, a second switching port connected to the valve hole of the second supplementary air bladder, a third switching port connected to the second switching port of the first pressure switch means, and a fourth switching port connected to the atmosphere 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic drawing show a spine massager according to the present invention. 
       FIG. 2(   a ) is a schematic drawing showing the spine massager of the present invention in action (I). 
       FIG. 2(   b ) is a schematic drawing showing the spine massager of the present invention in action (II). 
       FIG. 2(   c ) is a schematic drawing showing the spine massager of the present invention in action (III). 
       FIG. 2(   d ) is a schematic drawing showing the spine massager of the present invention in action (IV). 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIG. 1 , a spine massager in accordance with the present invention is shown comprised of a master air bladder  10 , a first supplementary air bladder  20 , a second supplementary air bladder  30 , a first pressure switch  40 , and a second pressure switch  50 . 
   The master air bladder  10  has an air chamber  11  and a valve hole  12 . The master air bladder  10  can be made in any of a variety of shapes, for example, a rectangular shape. According to this embodiment, the valve hole  12  is disposed in one corner of the air chamber  11 . The first supplementary air bladder  20  is provided at the top side of the master air bladder  10 , having an air chamber  21  and a valve hole  22  in one corner of the air chamber  21 .The second supplementary air bladder  30  is provided at the top side of the master air bladder  19  and at one lateral side of the first supplementary air bladder  20 , having an air chamber  31  and a valve hole  32  in one corner of the air chamber  31 . Preferably, the first supplementary air bladder  20  and the second supplementary air bladder  30  have a respectively part overlapped on each other. 
   The volume of the air chamber  21  of the first supplementary air bladder  20  is approximately equal to the air chamber  31  of the second supplementary air bladder  30  but smaller than the air chamber  11  of the master air bladder  10 . The master air bladder  10 , the first supplementary air bladder  20  and the second supplementary air bladder  30  are made from plastics, and sealed by a high-frequency sealing apparatus to for the respective air chambers  11 ,  21 ,  31 . 
   The first pressure switch  40  has a first air tube  41  connected to the valve hole  12  of the master air bladder  10 , a second air tube  42  connected to the second pressure switch  50 , and a third air tube  43  connected to an external air pump  60 . The second pressure switch  50  has a first air tube  51  connected to the valve hole  22  of the first supplementary air bladder  20 , a second air tube  52  connected to the valve hole  32  of the second supplementary air bladder  30 , a third air tube  53  connected to the first pressure switch  40 , and an exhaust hole  54 . According to the present preferred embodiment, the second air tube  42  of the first pressure switch  40  and the second air tube  52  of the second pressure switch  50  are the same air tube. 
   The operation of the spine massager is outlined hereinafter with reference to  FIGS. 2(   a ) through  2 ( d ) and  FIG. 1  again. As shown in  FIG. 2(   a ), the user  80  is lying on the floor or a flat surface  70 , and then the spine massager is inserted into the gap  82  between the user&#39;s back and the flat surface  70 . At this time, the spine of the user  80  rests at full length. 
   Thereafter, as shown in  FIG. 2(   b ), the third air tube  43  of the first pressure switch  40  is connected to the external air pump  80 , and then the air pump  80  is operated to pump air into the valve hole  12  to inflate the air chamber  11  of the master air bladder  10 . When the air chamber  11  of the master air bladder  10  reached the saturated status, the air pressure of the master air bladder  10  forces the first pressure switch  40  to switch off the valve (not shown) to the master air bladder  10  and to switch on the valve (not shown) to the first supplementary air bladder  20 , for enabling compressed air to pass from the air pump  80  to the air hole  22  of the first supplementary bladder  20  and to inflate the air chamber  21  of the first supplementary bladder  20 . At this time, the spine of the user  80  is forced by the inflated master air bladder  10  to curve upwards. 
   Referring to  FIG. 2(   c ), after the air chamber  21  of the first supplementary air bladder  20  has been inflated to the saturated status, the air pressure of the first supplementary air bladder  20  forces the second pressure switch  50  to switch off the valve (not shown) to the fist supplementary air bladder  20 . At this time, the spine of the user  80  is forced by the inflated first supplementary air bladder  20  to curve upwards further. 
   Referring to  FIG. 2(   d ), immediately after the second pressure switch  50  switched off the valve to the first supplementary air bladder  20 , the second pressure switch  50  switches on the valve (not shown) to the second supplementary air bladder  30  to let compressed air pass from the air pump  80  to the air hole  32  of the second supplementary bladder  30  and to inflate the air chamber  31  of the second supplementary bladder  30 , and simultaneously to let air be exhausted from the air chamber  21  of the first supplementary air bladder  20  through the exhaust hole  54 . At this time, the spine of the user  80  is forced to curve upwards at another location by the inflated second supplementary air bladder  30 . After the second supplementary air bladder  30  has been inflated to the saturated status, the air pressure of the second supplementary air bladder  30  forces the second pressure switch  50  to switch on the valve to the air chamber  21  of the first supplementary air bladder  20  to inflate the first supplementary air bladder  20  and simultaneously to let air be exhausted from the air chamber  31  of the second supplementary air bladder  30  through the exhaust hole  54 . 
   As indicated above, during the use of the present invention, the master air bladder  10  is constantly kept in the saturated status, the first supplementary air bladder  20  and the second supplementary air bladder  30  are alternatively inflated and exhausted to stretch the user&#39;s spine alternatively, thereby effectively massaging the joints of the user&#39;s spine. 
   Although a particular embodiment of the invention has been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention.