Abstract:
A disposable lancing device is disclosed, which may not return to its initial state after projection of a lancet, thereby preventing infectious possibility due to voluntary reuse of the device.  
     The disclosed disposable lancing device for injecting a lancet into the skin by elasticity stored in an elastic member to obtain blood, comprising: an operating member having a lancet attached to the fore portion, and an elastic member connected to the rear portion; a body receiving the operating member and the elastic member; a pushing member maintaining the operating member with the elasticity stored in the elastic member; and a retreat-preventing means fixing the operating member not to move backward again after ejection.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a disposable lancing device to withdraw a blood sample for treatment, and more specifically, to a disposable lancing device which may not be reused after a lancet is projected.  
           [0003]    2. Description of the Prior Art  
           [0004]    Generally, a lancing device is used when a small amount of blood is withdrawn for blood type test or glycosuria examination in blood of diabetes while an injector is used when a large quantity of blood is withdrawn.  
           [0005]    [0005]FIGS. 1 and 2 are perspective and cross-sectional views of a conventional disposable lancing device. As shown in FIGS. 1 and 2, a lancet  35  is hold at the fore portion of an operating member  30 , and an elastic member  40  is engaged with the rear portion of the operating member  30 . The operating member  30  has a protruding portion  32  at its rear portion. The protruding portion  32  is fixed by a lower end sloping side  22  which is inserted toward the inside of a body  10  and formed having a single unit with a pushing member  20  attached to the outside of the body  10 . When the pushing member  20  is pushed, the sloping side  22  is tilted to release the fixed operating member  30 , and then the operating member  30  is sprung toward due to elasticity stored in the elastic member  40 . As a result, the lancet  35  hold at the fore portion of the operating member  30  is shot from the body  10 . However, in the conventional disposable lancing device, if a user pushes the operating member  30  backward voluntarily, the sloping side  22  of the pushing member  20  can be pushed by the protruding portion  32  of the operating member  30 , and the protruding portion  32  can return to its initial state. Thereafter, the sloping side  22  of the pushing member  20  also returns to the initial state due to elasticity stored in the spring member  40  such that the operating member  30  is fixed to the pushing member  30  with the same elasticity as the initial state. Accordingly, although it is easy for the user to reuse the disposable lancing device voluntarily, the used lancing device has sanitary problems such as infection.  
         SUMMARY OF THE INVENTION  
         [0006]    In order to overcome the above-described problem, the present invention has an object to provide a disposable lancing device, which may not return to its initial state after projection of a lancet, thereby preventing infectious possibility.  
           [0007]    The present invention has another object to provide a disposable lancing device, which can be easily assembled due to the reduced number of components and conveniently used due to its controllable ejection length of the lancet.  
           [0008]    In order to accomplish the above-described objects, there is provided a disposable lancing device for injecting a lancet into the skin by elasticity stored in an elastic member to obtain blood, comprising: an operating member having a lancet attached to the fore portion, and an elastic member connected to the rear portion; a body receiving the operating member and the elastic member; a pushing member maintaining the operating member with the elasticity stored in the elastic member; and a retreat-preventing means fixing the operating member not to move backward again after ejection.  
           [0009]    The retreat-preventing means comprises a wing plate formed on a certain portion of the operating member, and a sloping plate formed in the body parallel with the wing plate, wherein the wing plate is placed at the rear of the sloping plate when elasticity is stored in the elastic member due to retreat of the operating member, and the wing plate is interlocked by the sloping plate after ejection of the operating member, thereby preventing the operating member from moving backward.  
           [0010]    The wing plate is formed aslant such that the end portion of the wing plate is toward the rear portion of the body, and the sloping plate is formed aslant such that the end portion of the sloping plate is toward the fore portion of the body.  
           [0011]    A cap for ushering ejection of the lancet and regulating the gap between the body and the cap by rotation is attached to the fore portion of the body, wherein the gap between the cap and the body is regulated by movement of a helical internal thread formed in the cap according to a helical groove formed in the body. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    The present invention will be explained in terms of exemplary embodiments described in detail with reference to the accompanying drawings, which are given only by way of illustration and thus are not limitative of the present invention, wherein:  
         [0013]    [0013]FIG. 1 is a perspective view of a conventional disposable lancing device;  
         [0014]    [0014]FIG. 2 is a cross-sectional view of the conventional disposable lancing device;  
         [0015]    [0015]FIG. 3 a  is a perspective view of a disposable lancing device according to the present invention;  
         [0016]    [0016]FIG. 3 b  is a exploded perspective view of the disposable lancing device according to the present invention;  
         [0017]    [0017]FIG. 3 c  is a cross-sectional view of the disposable lancing device according to the present invention;  
         [0018]    [0018]FIG. 4 a  is a cross-sectional view of the disposable lancing device according to the present invention, wherein a cap adheres closely to a body;  
         [0019]    [0019]FIG. 4 b  is a cross-sectional view of the disposable lancing device according to the present invention, wherein the cap is detached from the body;  
         [0020]    [0020]FIG. 5 a  is a cross-sectional view of the assembled disposable lancing device according to the present invention;  
         [0021]    [0021]FIG. 5 b  is a cross-sectional view of the disposable lancing device according to the present invention, wherein an operation member is fixed backward;  
         [0022]    [0022]FIG. 5 c  is a cross-sectional view of the disposable lancing device according to the present invention, wherein a wing plate passes a sloping plate;  
         [0023]    [0023]FIG. 5 d  is a cross-sectional view of the disposable lancing device according to the present invention, wherein a lancet is ejected to the utmost;  
         [0024]    [0024]FIG. 5 e  is a cross-sectional view of the disposable lancing device according to the present invention, wherein the wing plate is interlocked by the sloping plate; and  
         [0025]    [0025]FIG. 6 is a cross-sectional view of another example of a disposable lancing device according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0026]    The present invention will be described in detail with reference to the accompanying drawings.  
         [0027]    [0027]FIGS. 3 a ,  3   b  and  3   c  are perspective, exploded perspective and cross-sectional views of a disposable lancing device according to the present invention.  
         [0028]    As shown in FIGS. 3 a ,  3   b  and  3   c , the disclosed disposable lancing device comprises an operating member  140 , a pushing member  120 , bodies  110   a  and  110   b  and a cap  160 . The operating member  140  has a lancet  150  attached to its fore portion and an elastic member  130  combined with its rear portion. The pushing member  120  fixes the operating member  140  with the elasticity stored in the elastic member  130  while the lancing device is not used. The bodies  110   a  and  110   b  equipped with the pushing member  120  receive the operating member  140  and the elastic member  130  therein. The bodies  110   a  and  110   b  have the cap  160  at the fore portion (at the left side of Figs.) for ushering the ejection of the lancet  150  and regulating the gap between the bodies  110   a  and  110   b  and the cap by rotation.  
         [0029]    The operating member  140  is formed to move forward and backward within the bodies  110   a  and  110   b . The end of the elastic member  130 , which is attached to the rear portion of the operating member  140 , is fixed to a fixing groove  112  of the body. If the operating member  140  is pushed into the body, elasticity is stored in the elastic member  130 . In order to maintain this state, a protruding portion  142  formed on a certain portion of the operating member  140  is fixed by a latch  122  of the pushing member  120 .  
         [0030]    The pushing member  120  formed in the body  110   a  has the wedge-shaped latch  122  to the rear portion. As the operating member  140  moves backward, and the protruding portion  142  passes the latch  122 , the elastic member  120  is retracted. In this state, when the latch of the pushing member  120  is pressed down, the latch  122  is latched onto the protruding portion  142  at its retreat state. That is, the operating member  140  is fixed with elasticity stored in the elastic member  130 .  
         [0031]    A wing plate  145  formed aslant on a certain portion of the operating member  140 , and a sloping plate  115  formed in the body parallel with the wing plate  145  serve for prevention of reuse of the disclosed lancing device. The operating principles of the wing plate  145  and the sloping plate  115  will be explained referring to FIGS. 4 a  to  4   e.    
         [0032]    A stop projection  144  is formed on the fore portion of the operating member  140  to which the lancet  150  is attached. Since the stop projection  144  cannot pass through a hole  114  of the body, when the operating member  140  is moved forward by elasticity and inertia force, the ejected length of the lancet can be maintained at its regular length.  
         [0033]    However, since the disclosed lancing device comprises the cap  160  for regulating the gap between the cap  160  and the body, the ejected length of the lancet  150  to pierce the skin can be changed by regulating the cap  160 .  
         [0034]    [0034]FIG. 4 a  is a cross-sectional view of the disposable lancing device according to the present invention, wherein the cap adheres closely to the body, and FIG. 4 b  is a cross-sectional view of the disposable lancing device according to the present invention, wherein the cap is detached from the body.  
         [0035]    In order to regulate the ejected length of the lancet to pierce the skin, as shown in FIG. 3 b , a neck portion  117  formed in the fore portion of the bodies  110   a  and  110   b  has a helical groove  119  on its surface. When the cap  160  is fit into the neck portion  117 , a helical internal thread  162  formed in the cap  160  is screwed into the helical groove  119  formed in the neck portion  117 . The helical internal thread  162  moves according to the helical groove  119  by rotation of the cap  160 . As a result, the gap between the cap  160  and the body can be regulated. As shown in FIG. 4 b , if the cap becomes more distant from the body, the inserted length of the lancet  150  (the ejected length of the lancet from the cap) becomes shorter. However, as shown in FIG. 4 a , if the cap adheres closely to the body, the inserted length of the lancet  150  becomes longer.  
         [0036]    [0036]FIGS. 5 a  to  5   e  are views illustrating the operating principle of the disposable lancing device according to the present invention. FIG. 5 a  is a cross-sectional view of the assembled disposable lancing device. FIG. 5 b  is a cross-sectional view of the disposable lancing device, wherein an operation member is fixed backward. FIG. 5 c  is a cross-sectional view of the disposable lancing device, wherein a wing plate passes a sloping plate. FIG. 5 d  is a cross-sectional view of the disposable lancing device, wherein a lancet is ejected to the utmost. FIG. 5 e  is a cross-sectional view of the disposable lancing device, wherein the wing plate is interlocked by the sloping plate.  
         [0037]    Referring to FIGS. 5 a  to  5   e , if the elastic member  130  is put into the operating member  140 , and the end portion of the elastic member  130  is fixed at the fixing groove  112  of the body, the wing plate  145  is located at the rear portion of the sloping plate  115  formed in the body. In this state, the disclosed disposable lancing device is assembled (see FIG. 5 a ). When a user uses the disclosed disposable lancing device, the user pushes a protecting cap  152  connected to the fore of the operating member  140 , and then the operating member  140  is pushed into the body. In this state, as described in FIG. 3 c , if the user presses down the rear portion of the pushing member  120 , the protruding portion  142  of the operating member  140  is locked by the latch  122  of the pushing member  120  such that the operating member  140  is fixed backward (see FIG. 5 b ). In this state, if the user removes the protecting cap  152  and pushes the fore portion of the pushing member  120 , the locking between the operating member  140  and the pushing member  120  is released such that the operating member  140  and the lancet  150  is ejected by the expansion of the elastic member  130 .  
         [0038]    Under the same state as FIG. 5 b , the wing plate  145  is located to the rear end portion of the sloping plate  115 . When the pushing member  120  is pushed, the operating member  140  is protruded toward due to elasticity and inertia force of the elastic member  130 . In this process, because the operating member  140  passes the sloping plate  115  with the end of the wing plate  140  bent down (see FIG. 5 c ), the operating member  140  does not receive any resistance but moves until the stop projection  144  touches the internal wall of the hole  144  (see FIG. 5 d ). When the stop projection  144  touches the internal wall of the hole  144 , the inertia force is removed and the elastic member  130  is re-contracted, thereby retreating the operating member  140 . Since the wing plate  145  is restored into the original shape when the operating member  140  is retreated is interlocked by the sloping plate  115 . As a result, the operating member  140  is no longer retreated due to the wing plate  145  interlocked by the sloping plate  115 , as shown in FIG. 5 e . Although a user tries to retreat the operating member in this state, the user cannot retreat it because the wing plate  145  is interlocked by the sloping plate  115 . As a result, the disclosed lancing device cannot be reused by any user voluntarily.  
         [0039]    [0039]FIG. 6 is a cross-sectional view of another example of the disposable lancing device according to the present invention. As shown in FIG. 6, if the disclosed lancing device comprises two or more wing plates  145  and corresponding sloping plate  115 , it can have more powerful interlocking force between them.  
         [0040]    As discussed earlier, the disclosed disposable lancing device comprises the operating member which cannot be put into the body after ejection of the lancet because the wing plate formed on the operating member is placed at the fore portion of the sloping plate formed in the body. Accordingly, a user cannot put the lancet into the device voluntarily, thereby preventing the reuse of the lancing device.  
         [0041]    Additionally, the disclosed disposable lancing device is configured to load a spring after assembly and include the pushing member formed in the body, thereby having an excellent assembling characteristic.