Abstract:
A liquid delivery wand includes a centrally located fluid storage chamber. An absorbent pad is located within the working end of the wand for applying the treatment liquid to the skin while a vacuum is applied to the skin through an abrasive coated treatment tip. Coaxial, cylindrical tubes with flow channels between tube surfaces control the flow rate, the pressure drop being established by the close fit and length of adjacent surfaces of the coaxial components. The flow rate of the liquid is adjustable by simply rotating the interfitting components. The chamber that holds the liquid is sealed from the atmosphere at the distal and proximal end. When the wand is connected to vacuum and the distal end contacts the skin, the vacuum applies a negative pressure to the fluids within a fluid chamber. A small portion of liquid is thus transferred to wet the filter pad.

Description:
This application claims benefit of U.S. Provisional Application 61/264,526 filed Nov. 25, 2009. 
    
    
     Disclosed herein is a device and system for providing a skin treatment utilizing a skin enhancing fluid delivery system to provide both skin exfoliation using an abrasive coated working surface and skin hydration during one treatment. 
     BACKGROUND 
     Waldron U.S. Pat. No. 6,241,739, incorporated herein in its entirety by reference herein, shows the basic concept of a micro-dermabrasion system using an abrasive surface and vacuum to remove the outer layer of skin.  FIG. 11  of the patent shows a method of connecting a fluid source to the microdermabrasion instruments. 
     U.S. Pat. No. 6,500,183 (Waldron) describes a device using a rotating abrasive disc, vacuum and irrigation fluid to abrade the skin during the procedure. However, that patent does not show capturing the irrigation fluids. This design is intended for aggressive dermabrasion of patients with burns or scars where the fluids are intended to remove dead skin and other debris. 
     US Published Patent Application 2009/0222023 (Karasiuk) describes a micro-dermabrasion device where the fluids are stored in a secondary bottle and delivered to the hand piece through a tube. This type of product delivery inherently wastes the product in the tubing and is difficult to clean after the treatment. 
     US Published Patent Application 2009/0062815 (Karasiuk) describes a hand held instrument for micro-dermabrasion where the abrasive surfaces wiggle back and forth and skincare product is ejected onto the skin from a chamber and through tubing. The force to eject the fluid is a spring-actuated plunger. 
     U.S. Pat. No. 6,695,853 (Karasiuk) describes a micro-dermabrasion device where fluids are delivered to the skin via a tube from a remote container. The vacuum which contacts the skin is exterior to the abrasive surface. 
     US Published Patent Application 2009/0177171 (Ignon) describes a micro-dermabrasion device that uses a secondary storage container for the skincare products which is delivered to the instrument through a secondary tube. 
     U.S. Pat. No. 6,942,649 (Ignon) describes an instrument to apply dry material in coordination with an abrasive surface and vacuum. The abrasive surface is in the center of the instrument and the vacuum is on the periphery of the abrasive surface. 
     U.S. Pat. No. 6,527,783 (Ignon) and U.S. Pat. No. 6,592,595 (Ignon) use aluminum oxide as an abrasive material. 
     U.S. Pat. No. 6,629,983 (Ignon) uses abrasive pads. There is no mention of skincare product application. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a liquid applicator incorporating features of the invention. 
         FIG. 2  is a longitudinal cross section view of the liquid applicator of claim one, including a skin contacting pad prior to attachment to the applicator. 
         FIG. 3  is an expanded view of the applicator of  FIGS. 1 and 2 . 
         FIGS. 4-6  are cross section views of the liquid applicator showing the highest flow arrangement. 
         FIG. 7  is a longitudinal cross section of the liquid applicator.  FIG. 4  is a cross section through the wand tip taken along line  4 - 4  of  FIG. 6  and  FIG. 5  is a cross section through the front seal taken along line  5 - 5  of  FIG. 6 . 
         FIGS. 7-9  are cross section views of the liquid applicator showing an intermediate flow arrangement.  FIG. 9  is a longitudinal cross section of the liquid applicator.  FIG. 7  is a cross section through the wand tip taken along line  7 - 7  of  FIG. 9  and  FIG. 6  is a cross section through the front seal taken along line  8 - 8  of  FIG. 9 . 
         FIGS. 10-12  are cross section views of the liquid applicator showing the lowest flow arrangement.  FIG. 12  is a longitudinal cross section of the liquid applicator.  FIG. 10  is a cross section through the wand tip taken along line  10 - 10  of  FIG. 12  and  FIG. 11  is a cross section through the front seal taken along line  11 - 11  of  FIG. 12 . 
         FIG. 13  is a partially expanded longitudinal cross sectional view of the applicator of  FIG. 2  partially filled with fluid. 
         FIG. 14  is an assembled longitudinal cross sectional view of the applicator of  FIG. 2  applied to a skin surface while a vacuum is also applied to the skin surface. 
         FIG. 15  is an assembled longitudinal cross sectional view of the applicator of  FIG. 2  applied to a skin surface during fluid deliver. 
         FIG. 16  is view of the exterior surface of the distal portion of the vacuum tube. 
         FIG. 17  is a schematic diagram of a fluid delivery and skin treatment system incorporating the fluid applicator of  FIGS. 1-11 . 
     
    
    
     SUMMARY 
     Skin care products and serums are expensive and must be applied with minimum waste. They also must be applied uniformly. To do so, a liquid delivery wand includes a centrally located fluid storage chamber and an absorbent pad located within the working end of the wand for applying the treatment liquid to the skin while a vacuum is applied to the skin through the application tip. The skin is stretched partially into the center chamber and contacts the pad containing the liquid treatment. Only very small amounts of skincare product are lost to the vacuum system as a result of this arrangement. 
     The entire wand can be disassembled for cleaning and sterilization after treatments. There are no small orifices such as needle valves to control fluid flow rates. Coaxial, cylindrical tubes with flow channels between tube surfaces control the flow rate, the pressure drop being established by the close fit and length of adjacent surfaces of the coaxial components. The components are configured to have an adjustable flow rate of the liquid by simply rotating the interfitting components. To conserve expensive skincare products the chamber that holds the liquid is sealed from the atmosphere at the distal end. When the wand is connected to vacuum and the distal end contacts the skin, the vacuum applies a negative pressure to the fluids within a fluid chamber. A small portion of liquid is thus transferred to wet the filter pad. When the pressure (vacuum) equalizes, which occurs quickly, the liquid stops flowing. Minimal or no treatment fluid is lost to the vacuum tube, as air instead of liquid is sucked in to the vacuum line when the device is partially occluded or lifted from the skin. Flow from the storage chamber through into the pad can only occur when the tip of the delivery wand is fully occlude by the skin surface, said flow ceasing as soon as the pressures are equalized creating a sealed chamber. 
     The use of the instrument shortens the time of the treatment by doing both the dermabrasion and applying the treatment solution at the same time. The use of vacuum to apply the solution insures a deeper penetration of the solutions into the tissue. Common skincare products for use in the device are vitamins, hydrating solutions or serums. 
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-3 , a device incorporating features of the invention is shown.  FIG. 1  is a side view showing the liquid delivery wand  10 .  FIG. 2  is a cross sectional view of the wand  10  of  FIG. 1  and  FIG. 3  is an exploded cross-sectional view of the wand  10 . The wand  10  comprises a tubular cylinder  12  having, a front seal  16 , a wand tip  14  rotationally mounted within the front seal  16  and a rear seal  18  on the opposite end of the cylinder  12  to form an enclosed space  20  between the front and rear seals  16 , 18 . The distal surface of the wand tip has an abrasive surface  34 , preferably formed by diamond crystals permanently bonded thereto such as shown in applicant&#39;s prior U.S. Pat. Nos. 6,241,739 and 6,500,135, said patents incorporated herein, in their entirety, by reference. Alternatively, the wand tip can be coated with other abrasive substances or left uncoated A vacuum tube  22  has a distal end within a hole longitudinally through the center of the wand tip  14  and into a pad chamber  15  in the wand tip  14  and extends distally into the pad chamber  15  through the front seal  16 , the enclosed space  20 , and through the rear seal  18  with a proximal end extending outward for attachment to a vacuum source (not shown). The outer diameter of the vacuum tube at the point where it passes through the front seal and the wand tip is just slightly smaller than the inner diameter of those two components so that flow of fluid held within the enclosed space  20  is substantially restricted but for the grooves  30 ,  36  and  40 . A filter pad  24  is located within the wand tip  14 . Preferably the filter pad  24  has a central hole  32  which coincides with the distal end of the vacuum tube  22 . In use, the fluid in the delivery wand  10  passes into the pad chamber  15 , the pad  24  and onto the skin surface being treated. Each of the front seal  16 , rear seal  18  and wand tip  14  have O-ring seals  25 , or similar sealing devices, to form a liquid tight seal with the component which is around it. For example, an O-ring seal  25  is located between the front seal  16  and the rear seal  18  in the first instance and the cylinder  12  as well as between the wand tip  14  and the front seal  16  as best shown in  FIG. 2 . The cylinder  12 , wand tip  14 , front seal  16  and rear seal  18  are reusable while the filter pad  24  is a single use disposable. The parts can be disassembled for cleaning between treatments as shown in  FIG. 3 . 
       FIG. 1  shows markings to indicate the flow rate comprising an indicator arrow  26  on the outer surface of the wand tip  14  and indicia  28  indicating flow settings on the outer surface of the front seal, as explained below. One of the three flow settings ( 1 ,  2  and  3  with only  3  being shown) is shown marked on the outer surface of the front seal  18 . The indicia on the front seal aligns with a longitudinal groove  30  on the inner surface of the front seal  18 , as shown in  FIGS. 5 ,  6 ,  8 ,  9 ,  11  and  12 . The indicator arrow  26  aligns with a longitudinal groove  36  on the inner surface of the wand tip  14 , as best shown in  FIGS. 4 ,  6 ,  7 ,  9  and  10 . The wand tip  14  can be rotated in relationship to the front seal  16  to control the fluid flow rate as explained below. While the indicator arrow  26  and the indicia  28  are marked on the surface of the tip  14  and front seal  16  respectively, for clarity in explaining fluid flow with reference to  FIGS. 4-12  their locations are shown in said Figures next to the components instead of on the adjacent surface thereof. 
     Referring to  FIGS. 4-12 , flow rate of the fluid from the enclosed space  20  through the wand tip  14  of the liquid delivery wand  10  is adjusted by applying a vacuum to the lumen of the vacuum tube  22  and rotating the wand tip  14  within the front seal  16 . Flow is maximized when the arrow  26  on the wand tip  14  is positioned pointing to the number  3  (indicia  28 ) on the front tip  16  as shown in  FIG. 1  and  FIGS. 4-6 . When so positioned the groove  30  on the inner surface of the front seal  16  aligns with the tip seal groove  36  on the inner surface of the wand tip  14 , the fluid flowing through the aligned grooves  30 ,  36 . This provides the maximum area for fluid flow. The cross sectional area of the groove available for fluid flow in a preferred embodiment is 0.0024 in 2  (1.5 mm 2 ). 
     Flow is reduced to an intermediate rate when the arrow  26  on the wand tip  14  is positioned pointing to the number  2  (indicia  28 ) on the front tip  16 . As shown in  FIGS. 7-9 , when so positioned the groove  30  on the inner surface of the front seal  16  only partially aligns with the tip seal groove  36  on the inner surface of the wand tip  14 , the fluid flowing through the partially aligned grooves  30 ,  36  being partially restricted by the reduced alignment. With the wand tip rotated 45 degrees from the maximum position, as shown in  FIG. 7 , towards the number  2  the area open for fluid flow is 0.0011 in 2  (0.7 mm 2 ). Of course various orientations other than 45 degrees from the maximum position can be used to provide various intermediate flow rates. 
     Flow is reduced to its lowest rate when the arrow  26  on the wand tip  14  is positioned pointing to the number  1  (indicia  28 ) on the wand tip  16 . The wand tip  16 , as shown in  FIG. 10 , is rotated 90 degrees from the maximum position for minimum flow. As shown in  FIGS. 10-12 , when so positioned the groove  30  on the inner surface of the front seal  16  does not align with the tip seal groove  36  on the inner surface of the wand tip  14 . However, as shown in  FIG. 16 , the outer wall of the vacuum tube  22  has a spiral groove  40 , with a depth of about 0.020 inches, along its outer surface. In this instance the flow is predominantly through the groove  40  on the vacuum tube  22  outer surface that is located adjacent the inner surfaces of the front seal  16  and the wand tip  14 . In this case the area open for fluid flow is 0.0008 in 2  (0.5 mm 2 ). 
       FIG. 15  shows the fluid path from the enclosed space  20 , along the aligned grooves  30 ,  36  in the maximum flow orientation and into the filter pad  24 . Even though a vacuum is applied to the vacuum tube  22 , the fluid is not drawn up the vacuum tube  22  because the end is sealed against the skin and no air can flow through the tube. When the handpiece is removed from the skin, such as shown in  FIG. 14 , air flows passed the tip and through the vacuum tube but the majority of fluid is still captured in the filter pad and remains in the enclosed space  20  because no vacuum is applied to the fluid therein. 
     Vacuum pressure also affects the flow rate of the fluid. A reasonable setting for fluids with the viscosity similar to water is minimum flow (a setting of “1” on the wand tip) and 8 in-hg negative pressure. For viscous fluids a setting of “3” and a vacuum of 10 in-hg gives a proper flow. However, one skilled in the art will recognize that the 0°, 45° and 90° orientation of the indicator arrow  26  are only suggested settings and any orientation within that range, or greater than 90°, can be used. However, further rotation will not further reduce flow. 
       FIG. 17  shows the schematic of a vacuum system  48  incorporating the liquid delivery wand  10 . The vacuum pump  50  typically has a variable output from zero to 25 in-hg. Setting between 5 to 12 in-hg are preferred. The vacuum pressure gauge  52  is included to monitor the vacuum pressure which is adjusted by the metering valve  54 . A filter  56  is included to remove debris from the vacuum air stream. 
     To use the device described above the liquid delivery wand  10  is opened by removing the wand tip  14  and front seal  16  as shown in  FIG. 13  and the treatment fluid is placed in the enclosed space  20 . The wand tip  14  and front seal  16  are then put back in place, a pad  24  is placed in the pad chamber  15  in the wand tip  14 , the vacuum is turned on and adjusted by occluding the wand tip  14  against a skin surface and the flow rate on the wand  10  is set. The wand  10  is then placed against the skin surface to be treated with the distal end partially occluded so that air is pulled into the wand tip  14 , through the central opening in the pad  24  and up the vacuum tube  22 . This also draws fluid from the enclosed space  20  into the pad  24 . The wand  10  is then used in a normal manner, such as shown in applicants prior U.S. Pat. Nos. 6,241,739 and 6,500,135, incorporated herein by reference, to perform skin abrasion accompanied by use of the treatment fluid  42 . 
     Using a closed cell rubber foam as a skin substitute various flow settings and vacuum levels, as listed below in Table 1, were tested. The wand was passed over the foam in 4-inch long strokes for twenty-five passes which is equivalent to a facial treatment over a typical 5-15 minute time span. The “Flow” listed below is the amount of treatment fluid delivered per the 5-15 minute procedure. 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Flow Rate Testing of the Fluid Delivery Wand. 
               
             
          
           
               
                   
                   
                 Vacuum Setting 
                 Flow 
                 Waste 2   
               
               
                 Test Fluid 1   
                 Wand Setting 
                 In-hg 
                 (CC) 
                 (CC) 
               
               
                   
               
             
          
           
               
                 LRS100 
                 1 
                 5 
                 0.25 
                 0.1 
               
               
                 LRS100 
                 2 
                 5 
                 0.3 
                 0.1 
               
               
                 LRS100 
                 3 
                 5 
                 0.5 
                 0.1 
               
               
                 LRS100 
                 1 
                 8 
                 0.75 
                 0.1 
               
               
                 LRS100 
                 2 
                 8 
                 1 
                 0.1 
               
               
                 LRS100 
                 3 
                 8 
                 1.5 
                 0.1 
               
               
                 Mineral Oil 
                 1 
                 5 
                 2 
                 1 
               
               
                 Mineral Oil 
                 2 
                 5 
                 4 
                 1 
               
               
                 Mineral Oil 
                 3 
                 5 
                 5 
                 1 
               
               
                   
               
               
                   1 LRS100 is a moderate viscosity skin treatment product comprising plant derived lipids (sphingolipids), anti-inflammatory agents, nutritional and moisturizing agents in emollient base available from Custom Dermaceuticals, Inc., Randolph, NJ. Mineral Oil viscosity is slightly greater than water. 
               
               
                   2 The waste liquids constituters the fluid that did not reach the filter and was accumulated along the walls of the tubular canister 12. 
               
             
          
         
       
     
     Other examples of treatment fluids include C-serum and Even Skintone Serum available from Ultraceuticals Pty Ltd of Gladesville NSW, Australia. However, these treatment fluids are merely representative of numerous other skin treatment fluids and lotions known to practitioners in the field may be used in the liquid delivery wand described herein.