Abstract:
A lancet body  15  is molded around a needle or blade, in which the inner end of the needle body which is unsharpened has an L-shape bend at the unsharpened end. The bend, when embedded in the plastic which forms the body of the lancet, secures the needle against removal. The method involves the bending substantially perpendicularly of the unsharpened end of the lancet needle or blade to be substantially perpendicular with the elongate body of the blade. The needle or blade is placed within a jig interiorly of the plastic mold. The jig includes spaced opposed clamps and a single orienting support to the bent portion of the needle. The body of the lancet is relieved in many areas to reduce material cost and has a molded tab cover eliminating a loose part such as a separate cover.

Description:
RELATED APPLICATION  
       [0001]    This application is a Divisional of U.S. patent application Ser. No. 10/223,141, filed Aug. 19, 2002, now allowed. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to lancets which are lancing devices primarily used to obtain capillary blood samples for various testing purposes, not the least of which is blood glucose in the case of diabetics where such testing may be done on a daily basis. The purpose of the lancet is to penetrate the epidermis to a sufficient depth in order to draw the necessary amount of blood needed for the test, and yet hold the penetration, scaring, and injury to the epidermis to the irreducible minimum.  
         BACKGROUND OF THE INVENTION  
         [0003]    The present invention has, by way of background, various lancing devices which hold the lancet needle, cover, and carrier. One such device is manufactured for ProCare LLC, and is submitted separately in a prior art disclosure. Basically, however, the lancing device contains a sliding barrel with a trigger button and a base support for the lancet. A lancet cover is provided which threadedly surrounds the lancet as it is positioned in the barrel. At the outer end is an adjustable comfort tip with a lancet cover having numerical indicia and an arrow which, by rotation of the cover, determines the empirical depth to which the needle will penetrate.  
           [0004]    Virtually all hypodermic syringes have siliconized needles to aid in insertion to reduce the pain of insertion and further penetration. Therefore, it is desirable to siliconize the lancet needle. This permits the needle to be easily dislodged from the lancet body. In addition, a significant amount of plastic is employed by the prior art for such devices to attempt to secure the needle or blade against dislodgement, and protect against dimensional irregularities.  
           [0005]    Therefore, what is needed is a lancet in which the needle portion is firmly embedded in the plastic body, secured against rotation, secured against linear removal, and yet permits the utilization of a minimal amount of plastic, which plastic may be of an inferior grade and therefore less expensive than most lancet bodies, while still providing the sanitary and dimensional support necessary.  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention derives from the molding of a lancet body around a needle or blade, in which the inner end of the needle body which is unsharpened has an L-shape bend. As a result of the L-shape bend, when embedded in the plastic which forms the body of the lancet, the needle can neither rotate nor be removed linearly. In short, the needle is permanently immobilized against movement within the body of the lancet, within the X, Y and Z directions. The method of the present invention involves the bending substantially perpendicularly of the unsharpened end of the needle or blade to be substantially perpendicular with the elongate body of the blade. The thus formed needle or blade is placed within a jig interiorly of the plastic mold which is used to form the lancet body and the cover, with the cover surrounding the entirety of the sharpened portion of the needle or blade. The jig includes spaced opposed clamps and a single orienting support to the bent portion of the needle. Also, the body of the lancet is relieved in many areas and has a molded tab cover thereby reducing the plastic used and eliminating a loose part such as a separate cover.  
           [0007]    In view of the foregoing it is a principal object of the present invention to provide an apparatus and method for forming a lancet in which the needle or blade is securely positioned against any dislodgement, whether by rotation, or by linear movement within the lancet body.  
           [0008]    A further object of the present invention is to provide such a lancet in which rotation and longitudinal dislodgement are prevented, which can accommodate a relatively low grade form of plastic and yet present in operation a dimensionally stable lancet, fully sanitary, for use with the typical user&#39;s home care kit.  
           [0009]    A further object of the present invention is addressed to a method of forming a lancet body and needle or blade with a cover head on a highly cost effective basis attributable to the lack of necessity for special purpose jigs to control the position of the needle or blade within the lancet body. As a result, a further objective is achieved by providing the bent leg or L-shaped end portion so that it can be precisely positioned interiorly in the mold, and the plastic body of the lancet molded around the needle or blade with the offset anchor resulting in a product which is dimensionally accurate to tolerances which are acceptable and heretofore unknown on the quantities produced for the disposable lancet market. 
       
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS  
       [0010]    Further objects and advantages of the present invention will become apparent as the following description proceeds, taken in conjunction with the accompanying illustrative drawings in which:  
         [0011]    [0011]FIG. 1 is an exploded partially perspective view of a typical home lancing device showing the lancet in a mid-portion of the figure;  
         [0012]    [0012]FIGS. 2A, 2B,  2 C,  2 D,  2 E,  2 F and  2 G, show the utilization of the device typically by the patient applying the lancet to his/her own finger;  
         [0013]    [0013]FIG. 3 is a perspective partially broken exploded view of the subject lancet showing the needle or blade interiorly thereof in its secured position;  
         [0014]    [0014]FIGS. 4A and 4B are two views of the lancet needle which is molded into the body portion of the lancet;  
         [0015]    [0015]FIG. 5 is a front elevation of the lancet;  
         [0016]    [0016]FIG. 6 is a side elevation of the lancet;  
         [0017]    [0017]FIG. 7 is a transverse sectional view of the lancet taken at  7 - 7  of FIG. 5;  
         [0018]    [0018]FIG. 8 is a plan view, partially diagrammatic and partially broken, of the lower portion of the mold utilized to form the subject lancet;  
         [0019]    [0019]FIG. 9 is a transverse sectional partially diagrammatic view, in enlarged scale, taken along section line  9 - 9  of FIG. 8; and  
         [0020]    [0020]FIG. 10 is yet another transverse sectional view taken from FIG. 8 at section line  10 - 10  showing the support for the angled base anchor  26  of the needle  25 . 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]    In the preferred embodiment, as illustrated in FIG. 1, the lancing device  10  is used to obtain a capillary blood sample needed for blood glucose monitoring or for other tests requiring one or two drops of blood. The adjustable comfort tip  11  on the lancing device  10  permits choosing the best depth for skin penetration. As shown, there are five discrete positions  12  which can be utilized by the self-user.  
         [0022]    As shown in FIGS. 2A through 2G, the needle cover  21  is twisted off of the lancet device  10 , the new lancet  20  is thereafter inserted into the lancet carrier  15 , the needle cover  21  is removed thereafter revealing the needle  25 , the lancet lancing device then has the comfort tip  11  placed in position. At this point, rotation of the adjustable comfort tip  11  offers a plurality of levels of skin penetration (see FIG. 2E). The user empirically determines which of these is best for his use.  
         [0023]    The lancing device  10  is cocked by slowly pulling the slide barrel  14  away from the lancing device cover. A click indicates audibly when the carrier is locked in position. Thereafter the end of the adjustable comfort tip is pressed against the finger, the trigger button  16  is engaged, and the lancing device needle tip sharpened end  28  penetrates the epidermis to a point where the one or two drops of blood needed can be drawn.  
         [0024]    Turning now to FIG. 3. which is an exploded perspective view, it can be seen that the two principle components of the lancet itself are the body  22  and the needle cover  21  cap which are the molded portions, and the needle or blade  25  which is the metal portion.  
         [0025]    Important to the invention, and particularly shown in FIGS. 3, 5 and  8 , is the configuration of the needle or blade  25  in which the end opposite the sharpened end  28  has been bent at an angle with the needle body  29 . Desirably the bend is perpendicular to the main body  29 . Such a bend to form an anchor  26  critical to the present invention in that, by providing the offset, once the needle is molded into the body of the lancet it cannot be moved longitudinally, nor can it be rotated, nor can it be moved sideways in any direction. By virtue of the angled base anchor  26 , the needle or blade  25  is permanently, dimensionally and sanitarily positioned inside the lancet body with the needle cover in place but removable by twisting to dislodge, basically as described in FIG. 3 above. The method of the present invention will become more apparent as the description of the body  22  of the lancet proceeds. As can be seen in FIGS. 5 and 6, there are four runners  30  which, in cross-section, give a cruciform appearance, as shown in FIG. 7. There are two uninterrupted runners  31 , and two interrupted runners  32 . The interrupted runners  32  are formed when the opposed prongs of a vise are positioned in place interiorly of the mold to securely engage the needle prior to injecting the plastic. In this fashion the position of the needle is ensured and when the vise elements are withdrawn from the body  22 , ports are revealed which reduce the amount of plastic employed, and simultaneously permit the user to see and observe the needle interiorly of the body  22 .  
         [0026]    While dimensions and composition materials do not form a key portion of the invention, those used in a commercial embodiment are illustrative of successful dimensions. All dimensions are in millimeters. As noticed particularly in FIGS.  5 , and  6  the entire lancet is 32 mm in length. The body portion is 20.7 mm, plus or minus 2 mm. The thickness dimension, taken from the tips of the runners, is 6.3 mm.  
         [0027]    The needle, as shown in FIGS. 4A and 4B, is 24.4 mm in length, plus or minus 2 mm. The bent leg is 1.8 mm in length taken from the far side of the body portion. As shown in FIG. 4A, there is double-bevel at the sharpened end  28  of the needle. The material ideally employed is stainless steel 1CR18NI9.  
         [0028]    The material employed for the plastic body is LDPE, better known as “low density polyethylene” blended with HDPE, better known as “high density polyethylene”. Virgin or reground may be used. Runners and flashing are reground and may be used exclusively or blended with virgin material.  
         [0029]    While dimensions are not considered critical, they illustrate the precision involved. The total overall length of the lancet, including the cover, is 32 mm. The diameter at the largest portion of the body across the top of opposed runners is 6 mm. The total diameter of the tip or cap portion is 9.4 mm, and its thickness is 3.5 mm.  
       THE METHOD  
       [0030]    The method of the present invention involves developing a mold  34  for a plurality of needles  25  in connection with a multiple cavity mold in which the needle or blade are positioned so that the same can be an interior portion of the completed lancet  20  when the plastic is injected into the recess which surrounds the carrying portion of the bent angle needle or blade. In this connection, it will be seen in FIG. 5 that the needle body  22  actually shows interiorly of the lancet body  20  because the support which holds the needle is surrounded by plastic, when the support is removed the needle appears. On the opposite side the needle is similarly viewed through much smaller ports. The reason for the smaller ports is that they contain a pin which clampling engages the needle on the post support of the jig interiorly of the mold to thereby firmly position the needle to be encapsulated in the plastic which is thereafter molded around the needle or blade.  
         [0031]    Specifically as shown in FIG. 8, a multiple cavity mold  34  is intended for forming the lancet  20 . As shown here there are 20 cavities, ten on each side. Specific details of two cavities are shown in the upper right corner of FIG. 8. Turning now to FIG. 9, it will be seen that a clamping assembly  40  is used to engage the main body  29  of the needle  25 . The lower jaw  41  of the clamping assembly  40  is somewhat larger than the upper jaw  42  of the same clamping assembly. The needle  25  is positioned on top of the lower jaw  41  prior to molding. At or about the same time, the angled base anchor  26  of the needle  25  is positioned on top of the anchor support  44 . When the upper portion of the mold is placed over the lower portion, and the plastic is injected, the needle  25  and its components are securely held in place by the clamping assembly  40 . After the plastic has sufficiently cooled, the two mold supports are removed and the lancets  20  removed from the mold. Specifically as shown in FIG. 5, it will be seen that the interrupted runners  32  have ports which remain exposing needle body. The vise ports  35  are large vise ports  36 , and small vise ports  38 . In addition, there is an anchor support port  45 , viewed particularly in FIG. 5, and in which the angled base anchor  26  of the needle  25  is exposed. This results from the withdrawal of the anchor support  44  when the upper and lower portions of the mold are separated.  
         [0032]    Summarizing the above, the method contemplates providing a mold having a plurality of cavities which are the mirror image of the lancet  20  to be molded. The next step in the process relates to providing clamping means, which are opposed, and which clampingly engage the needle body at spaced relationship. Finally, the step includes providing an anchor support at one end whereby the needle is not only supported on the anchor, but the anchor determines the position of the point of the needle within the molded lancet body cover. Thus, the sequencing, once the clamping means are provided within the mold, and the support means exist for the angled base anchor portion  26  of the needle  25 , the needles are inserted in the one portion of the mold on top of their respective supports, shown here as three in number (two for the needle body  25  and one for the angled base anchor  26 ). Thereafter the mold top is placed on the mold bottom, the clamping members engage the needle  25  in fixed relationship to the cavity to be filled with plastic. Once the plastic is within the balance of the cavity, the needle is positively oriented therein in relation to the base of the needle and the runners which, in turn, control the spaced relationship of the sharpened end  28  of the needle or blade  25  when positioned in a typical lancing device  10 , such as shown in FIGS. 1 and 2A through  2 G.  
         [0033]    It will be understood that various changes in the details, materials and arrangements of parts, or method which have been herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims.  
                                             PARTS LIST                                00   34 MULTIPLE CAVITY   68             MOLD       01   35 VISE PORTS   69       02   36 LARGE VISE PORTS (35)   70       03   37   71       04   38 SMALL VISE PORTS (35)   72       05   39   73       06   40 CLAMP ASSEMBLY   74       07   41 LOWER JAW   75       08   42 UPPER JAW   76       09   43   77       10 LANCING DEVICE   44 ANCHOR SUPPORT   78       11 COMFORT TIP   45 ANCHOR SUPPORT PORT   79       12 POSITIONS   46   80       13   47   81       14 SLIDE BARREL   48   82       15 LANCET CARRIER   49   83       16 TRIGGER BUTTON   50   84       17   51   85       18   52   86       19   53   87       20 LANCET   54   88       21 LANCET COVER (20)   55   89       22 NEEDLE BODY   56   90       23   57   91       24   58   92       25 NEEDLE OR BLADE   59   93       26 ANGLED BASE ANCHOR   60   94       27   61   95       28 SHARPENED END   62   96       29 MAIN BODY   63   97       30 RUNNERS (4)   64   98       31 UNINTERRUPTED   65   99         RUNNERS       32 INTERRUPTED RUNNERS   66   100       33   67   101