Abstract:
A hand-held percussive device for facilitating the redistribution of fat remaining after liposuction. A piston is driven pneumatically in a reciprocating motion externally against a patient&#39;s skin and is self-actuated. A floating valve works in cooperation with the piston such that when the device is pressed against a patient&#39;s skin, the reciprocating motion begins. When the device is retracted, the reciprocating motion stops.

Description:
FIELD OF INVENTION 
   This invention relates to generally to devices used to treat living bodies after surgery. This invention relates particularly to a noninvasive, pressure-actuated apparatus for applying percussions to a body to facilitate the redistribution of fat remaining after liposuction or to massage the body. 
   BACKGROUND 
   Liposuction involves inserting a cannula through small incisions in a body and vacuuming out fat cells. Typically the cannula is moved in a reciprocating motion in conjunction with a fan motion to remove the fat uniformly within a desired area. Ideally, deep pockets of fat, as opposed to the fat in the even superficial layer near the skin, is removed during liposuction. The fat remaining near the skin helps leave the skin with a smooth contour. However, sometimes the fat near the skin is absent naturally or removed during liposuction. To avoid contour irregularities such as dimpling or rippling, the fat that remains must be redistributed in a uniform manner, as well as replaced in some areas. To contour and give a better shape to a body, deep fat removed from one area may be deposited in another area. 
   Several methods have been developed to improve the texture of the skin and contour of the body after liposuction. Pressure dressings, girdles, or contouring garments are placed on a liposuction patient after surgery and may be worn for several days or weeks to help the skin adhere to the new shape and contract properly. It has been reported that liposuction patients have smoother skin if the skin is percussed, rolled or massaged by hand during or immediately after the surgery to redistribute the fat remaining after liposuction. These treatments have has other beneficial effects, as well, such as relaxing the patient. However, it is difficult for a practitioner to uniformly and continuously percuss or massage a patient at length, particularly in a relatively small area of the body, such as the area affected by liposuction. It is desirable to automate such a treatment. 
   Therefore, it is an object of this invention to provide an apparatus to massage a body be percussion. It is a further object of the invention to provide an apparatus that facilitates the redistribution of fat after liposuction. 
   SUMMARY OF THE INVENTION 
   The present invention is a hand-held percussive device for massaging a body and facilitating the redistribution of fat remaining after liposuction. A piston is driven by in a reciprocating motion externally against a patient&#39;s skin. The default position of the piston is in an “off” position, and the device is actuated when it is depressed against the skin of a patient. Preferably the piston is driven pneumatically and in the default “off” position the gas that drives the piston is exhausted through a port, away from the patient and practitioner. When the device is depressed against the skin of a patient, force is applied to the piston causing a floating valve that moves in concert with the piston to block the exhaust port. This redirects gas into the piston chamber and forces the piston out of the piston chamber. At its farthest extension, the floating valve unblocks the exhaust port, allowing the air to be redirected out, away from the piston allowing the piston to retract into the piston chamber. The cycle repeats itself as long as force is applied to the piston. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded view of a first embodiment of the present invention. 
       FIG. 2  is an exploded view of a second embodiment of the present invention. 
       FIG. 3  is a side view of the valve assembly. 
       FIG. 4  is a top view of the valve assembly and housing. 
       FIG. 5  is a cross-section view along line  5 — 5  of  FIG. 1  showing the housing and valve assembly with gas flowing into the piston chamber thereby forcing the piston out. 
       FIG. 6  is a cross-section view along line  5 — 5  of  FIG. 1  showing the housing and valve assembly with gas flowing out the exhaust port, allowing the piston to retract into the piston chamber. 
       FIG. 7  is a detailed cross-section of the valve assembly, piston, and housing (head mount guide aperture omitted from view). 
       FIG. 8  is a top view of the second embodiment showing the head and the head mount in fluid communication with the vacuum source. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to  FIGS. 1-8 , there is illustrated a first embodiment of the present invention, designated generally as  10 , wherein like numbers indicate like parts throughout. The device comprises a housing  11  which receives a piston  12  in an aperture referred to herein as a piston chamber  14 . A substantially air-tight seal is formed between the piston  12  and piston chamber  14  by seating a piston o-ring  15  in the detent formed by an annular piston ring  13  having a smaller diameter than the piston  12 .  FIGS. 3 and 4  show the piston o-ring  15  disposed about the piston  12 . 
   The housing  11  also has an aperture to receive a floating valve  16 , the aperture referred to herein as a valve chamber  17 . The valve chamber  17  and piston chamber  14  are in fluid communication at opening A, as indicated in FIG.  7 . The floating valve  16  is part of a valve assembly  18 , further comprising a pin  19  that fits loosely through an aperture in the housing  30 , through an aperture  20  in the floating valve  16  and protrudes into an aperture  21  in the piston  12 . This valve assembly  18  thereby causes the floating valve  16  and the piston  12  to move cooperatively and to be retained within the housing  11 . Preferably the pin  19  and piston aperture  21  are matedly threaded. 
   A series of substantially air-tight compartments are formed between the floating valve  16  and valve chamber  17  by seating several valve o-rings,  31 ,  32 ,  33 ,  34 , and  35  in the detents formed by annular valve rings,  41 ,  42 ,  43 ,  44 ,  45 , respectively, which have a smaller diameter than the floating valve  16 .  FIGS. 5 and 6  show the valve o-rings  31 - 35  disposed about the annular valve rings  41 - 45 .  FIG. 7  indicates the four compartments W, X, Y, and Z formed by the o-rings sealed against the valve chamber. 
   Referring now particularly to  FIGS. 5 ,  6 , and  7  the housing  11  has a inlet port  61  which is connected to a source of pressurized gas (not shown). The housing  11  has a primary exhaust port  63  and a secondary exhaust port  64 . The inlet port  61  is in fluid communication with a gas channel  62  which is in fluid communication with the valve chamber  17  at B. As shown in  FIG. 5 , when the piston  12  is retracted into the piston chamber  14 , the floating valve  16  is also in a retracted position. In the retracted position, the floating valve  16  blocks the gas flow to either exhaust port by positioning air-tight compartment X where the gas channel  62  opens into the valve chamber  17 , namely B. This position causes a direct channel to form between the gas channel  62  and the piston chamber  14 . Gas entering the inlet port  61  is thus directed into the piston chamber  14 , thereby forcing the piston  12  out of the piston chamber  14 . As soon as the pin  19  (which is stationery in the piston) comes in contact with the leading edge of the aperture  20  in the floating valve  16 , the floating valve  15  will be pulled out of the valve chamber  17  in concert with the piston  12  until pin  19  comes in contact with the leading edge of the housing aperture  30 . When the floating valve  16  is extended, compartment Y closes the gas channel  62  and simultaneously opens a channel between the piston chamber  14  and the primary exhaust port  63 . Gas is exhausted from the piston chamber  14 , allowing the piston  12  to retract into the piston chamber  14 . As soon as the pin  19  comes in contact with the trailing edge of the aperture  20  in the floating valve  16 , the floating valve will be retracted into the valve chamber  17  in concert with the piston  12 . This, in turn, again blocks the gas flow to either exhaust port by positioning compartment X at B, thereby directing gas into the piston chamber  14  and forcing the piston  12  out of the piston chamber  14 . The cycle will then repeat itself as long as a retracting force is applied to the piston  12 , as explained in more detail below. 
   The speed at which the device operates is partially dependent on the pressure of the incoming gas. At sufficiently high speeds, the gas in the valve chamber  17  will not have time to flow to the primary exhaust port  63  before the floating valve  16  completely retracts. For this reason, a secondary exhaust port  64  is formed in the housing  11 . The secondary exhaust port  64  allows gas in the valve chamber  17  to more quickly escape as the valve is displacing gas upon retraction. 
   While the preferred embodiment of the device is driven pneumatically, the reciprocating motion may also be driven electronically. In this embodiment, the piston  12  is in connection with an electrical source. A switch and means for biasing the piston in a reciprocal motion are in communication with the electrical source and the piston such that the electrical source and the switch cooperate to cause the piston to move in a reciprocating motion. 
   A head mount  22  is attached to the piston  12 , preferably by a threaded screw  23  in piston/head mount aperture  38 , although other means of attachment will suffice. A head  24  is attached to the head mount  22 . The head  24  is preferably oval in cross-section, but may take on other shapes or have a larger or smaller diameter that the head  24  shown herein. Because they are attached to each other, the head  24  and head mount  22  move in concert with the piston  12 . The head mount  22  has guides  36   a ,  36   b , and  36   c  that slide in head mount guide apertures in the housing,  37   a ,  37   b , and  37   c , respectively. 
   The head  24  is also removable and may be interchanged with other heads. In the preferred embodiment, the head  24  is attached to the head mount  22  by a compression fit. As shown in  FIGS. 1 and 2 , the head mount  22  has an extension  26  having an annular ring  27 . An o-ring  28  is seated in the annular ring of the extension  26 . The head  24  has a center aperture  29  that is slightly larger in diameter than the extension  26 , but smaller than the outside diameter of the extension o-ring. The head  24  is attached to the head mount  22  by forcing the center aperture  29  over the o-ring  28  fitted on the extension  26 , causing the o-ring  28  to compress and the extension to protrude through the center aperture  29 . In this manner the head  24  will stay attached to the head mount until it is pulled off with sufficient force to compress the o-ring  28 . 
   The device is pressure-actuated when the piston  12  is depressed as a result of pressing the head  24  against the patient&#39;s skin. The default position of the piston is in an “off” position, wherein the gas that drives the piston is exhausted through a port, away from the patient and practitioner. This starts the cycle describes above, namely that when the head is depressed against the skin of a patient, the floating valve blocks the exhaust ports, thereby redirecting air into the piston chamber and forcing the piston out of the piston chamber. At its farthest extension, the floating valve unblocks the exhaust port, allowing the air to be redirected out, away from the piston allowing the piston to retract into the piston chamber. The cycle repeats itself as long as force is applied to the piston. 
     FIGS. 2 and 8  shows a second embodiment of the invention. The head mount  22  has a channel  51  therein that enables fluid communication between the head  24  and a source of vacuum  52 . When the head  24  is pressed against the skin and the vacuum is turned on, the negative pressure gradient causes the skin to be sucked tightly against and slightly into the head  24 . 
   While there has been illustrated and described what is at present considered to be the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.