Abstract:
A retained needle structure of a comprises a syringe needle with one or more fastening portion, a catheter with a cannula having a flexible tube, as well as a syringe cover with an aperture and gliding portion. The syringe needle has an inserting portion which is axially operated by users to enhance safety practice in clinical use. First design is the sliding slot has a deflected slant portion at the distal end. When the fastening portion is at the rear end of sliding slot, the injection needle is already inside of syringe cover. At the same point, body of the syringe needle is deflected laterally from the center of the syringe cover. 
     The second design is used the levering effect from gravity of syringe cover. When the fastening portion is at the rear end of sliding slot, the syringe cover is vertically rotated from the original center of the syringe cover.

Description:
[0001]    The present invention is a continuation-in-part (CIP) of US application No. 10,569,623, and claims the priority filing date of Feb. 27, 2006. In the claims, claim  1  of the present application corresponds to both claim  1  and claim  3  of patent application; claim  4  corresponds to both claim  28  and claim  29  of patent application; claim  8  is a newly added claim; other claims in the present application are dependent claims. This invention relates to a user-friendly improvement on a retained needle structure, and particularly to a retained needle structure which is axially operated. 
     
    
     FIELD OF THE INVENTION 
     Description of the Prior Art 
       [0002]    The present invention is an improvement on U.S. Pat. No. 5,954,698, in which a catheter hub  110  and a needle protector  10  are fixed together with a screw, as illustrated by  FIG. 21 ; threads  20  and  130  of the needle protector  10  is locked in with threads of  132  and  114  of the catheter hub  110 . After the catheter hub  110  is injected into the blood vessel of patients, one can only take apart the catheter hub  110  from needle protector  10  by turning both of them around, which is an unreliable and tedious process. As opposed to a one-dimensional pulling movement, on-spot revolution may very likely shake the needle tip and hence cause rupture in blood vessels. 
         [0003]    The present invention is also an improvement on U.S. Pat. No. 5,456,668, in which the slot is of a straight form throughout, without utilizing levering principle (the gravity of the syringe cover) to vertically rotate the syringe cover from its original central position, requiring device  65  in  FIG. 8 , a device  4  in  FIG. 3 , or a spring in syringe needle. When the injection needle is in the syringe cover, the shank  32  in  FIG. 2  is breakable by manual operation to prevent the injection needle from being moved by the syringe needle back into the opening. The procedure needs two-handed operation. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention, as opposed to the radially operating needle structure in U.S. Pat. No. 5,954,698, can only be operated axially in an X-axis dimension, or in a horizontal way; it, therefore, effectively reduces undesired shift of needle movement resulting from 360 degrees of radial movements. 
         [0005]    The present invention, as opposed to U.S. Pat. No. 5,456,668, utilizes the fact that the gravity of the syringe cover is in the front when the fastening portion is at the rear end of sliding slot, so the syringe cover is vertically rotated. Another design is the sliding slot has a deflected slant portion at the distal end. When the fastening portion is at the deflected slant portion, the syringe needle is deflected laterally. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The drawings disclose several illustrative embodiments of the present invention which serve to exemplify the various advantages and objects hereof, and are as follows: 
           [0007]      FIG. 1  is the first preferred embodiment; 
           [0008]      FIG. 2   a  is a top view of the first preferred embodiment; 
           [0009]      FIG. 2   b  is a side view of the first preferred embodiment; 
           [0010]      FIG. 3   a  is a top view of the first preferred embodiment after operation; 
           [0011]      FIG. 3   b  is a side view of the first preferred embodiment after operation; 
           [0012]      FIG. 4  further illustrates the first preferred embodiment; 
           [0013]      FIG. 5  is the second preferred embodiment; 
           [0014]      FIG. 6   a  is a top view of the second preferred embodiment; 
           [0015]      FIG. 6   b  is a side view of the second preferred embodiment; 
           [0016]      FIG. 7   a  is a top view of the second preferred embodiment after operation; 
           [0017]      FIG. 7   b  is a side view of the second preferred embodiment after operation; 
           [0018]      FIG. 8  further illustrates the second preferred embodiment; 
           [0019]      FIG. 9  is the third preferred embodiment; 
           [0020]      FIG. 10   a  is a top view of the third preferred embodiment; 
           [0021]      FIG. 10   b  is a side view of the third preferred embodiment; 
           [0022]      FIG. 11   a  is a top view of the third preferred embodiment of the present invention after operation; 
           [0023]      FIG. 11   b  is a side view of the third preferred embodiment of the present invention after operation; 
           [0024]      FIG. 12  further illustrates the third preferred embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0025]    Referring to  FIG. 1 , a retained needle structure of the present invention comprises a syringe needle  1 , a catheter  2  and a syringe cover  3 . 
         [0026]    The syringe needle  1  has an inserting portion  11  at a front end. On the inserting portion  11  is inserted an injection needle  111 . On the syringe needle  1 , at least one fastening portion  12  is molded on one side and a ventilating filter  13  is at a rear end. The fastening portion  12  and syringe needle  1  is connected by a shank  33  (not shown in the figures). 
         [0027]    The catheter  2  has a cannula  21  with a flexible tube  22 . A stop portion  23  is disposed at an outer rim of a rear end of the cannula  21 . The catheter  2  is sleeved on the inserting portion  11  of the syringe needle  1 . The injection needle  111  of the syringe needle  1  is with the flexible tube  22  of the catheter  2 . An opening  31  is disposed at the front end of syringe cover  3  with a hook portion  311  (not shown in the figure). 
         [0028]    The syringe cover  3  has an aperture  31  formed at a front end. A plurality of hook portions  311 ,  312  are disposed at a front end of the syringe cover  3  (not shown in the figure). At least one gliding portion  32  extends on one side of the syringe cover  3  and corresponds to the fastening portion  12  of the syringe needle  1  in position and amount. On each of the gliding portions  32 , a sliding slot  321  is disposed. The front end of the syringe cover has a connection member connected with a lid (not shown in the figure). A deflected slant portion  323  is formed at the distal end of the sliding slot  321 . 
         [0029]    Referring to  FIG. 2 , before using, the hook portion  311  of the syringe cover  3  connects with the stop portion  23  of the catheter  2 ; in the meantime, the fasten portion  12  of the syringe needle  1  is placed at the front end of the sliding slot  321  of the syringe cover  3 , and the cannula  21  of the catheter  2  is fitted with the inserting portion  11  of the syringe needle  1 . 
         [0030]    Referring to the perspective top view of  FIG. 2   a , the diameter of the body of the syringe needle  1 , a 1 , is smaller than the inner diameter of the syringe cover  3 , b 1 , at the horizontal axis. Furthermore, there is a gap c 1  between the diameter a 1  and b 1 , as shown a (Enlarge view). The syringe needle  1  is in the frontal position of the syringe cover  3  now. 
         [0031]    Referring to the perspective side view of  FIG. 2   b , the diameter of the body of the syringe needle  1  is d 1  which coincides completely with the inner diameter of the syringe cover  3  at the vertical axis. It does not have any gap between them as illustrated in B-B section. The longitudinal axis of the injection needle  111  is coaxial with the longitudinal axes of the syringe needle  1  and the syringe cover  3 . 
         [0032]    The injection needle  111  penetrates the skin and vein of the patient and guides the catheter  2  into the vein. At the same time, the catheter  2  moves forward. Because a plurality of hook portions  311 , 312  as illustrated in A-A section are disposed at a front end of the syringe cover  3 , they also connect with the catheter  2  by the stop portion  23 . So the stop portion  23  of the catheter  2  moves syringe cover  3  forward, Once the catheter is in position, the fastening portion  12  of the syringe needle  1  is withdrawn along the sliding slot  321  of the syringe cover  3 . When fastening portion  12  enters the slant portion  323 , the injection needle  111  is already inside of the syringe cover  3 . It means the injection needle  111  is located at the back of the hook portion  311 . At the same time, the stop portion  23  of catheter  2  is disconnected from hook portion  311  of syringe cover  3  ( FIG. 3 ). As shown by  FIG. 3   a , at this time, body of the syringe needle  1  is no longer in the center position of syringe cover  3 , but is deflected from the center; as a result, the injection needle  111  is deflected from center position too. Finally, the injection needle  111  shifts to the right and behind the hook portion  311  of the syringe cover  3 . A salient  322 , positioned at the rear end of the sliding slot  321  or on slant portion  323 , bars forward movement of the fastening portion  12  when the fastening portion  12  enters the slant portion  323 . It is very difficult to exposes the injection needle  111  outside of the syringe cover  3 . In  FIG. 3   a , the number  14  refers to the location of the syringe needle  1  in the sliding slot  321  without deflection, and the number  15  refers to the location of the syringe needle  1  in the slant portion  323 , as shown b (Enlarge view). 
         [0033]    Further referring to the side view of  FIG. 3   b , the syringe needle  1  is still in the center of the syringe cover  3  at the vertical axis. It means that the injection needle  111  deflects to the right side at horizontal direction and sits behind the hook portion  311  of the syringe cover  3 . We also can see the syringe needle deflects to the left side as shown in B-B section view. 
         [0034]    Further referring to  FIG. 4 , a reception slot  324  is disposed at the rear end of the slant potion  323  of the syringe cover  3 , which provides an extended protection when syringe needle  1  enters reception slot  324 ; i.e. the injection needle  111  would not be exposed outside of syringe cover  3 . 
         [0035]    Further referring to  FIG. 5 , a safe catheter structure is composed of a syringe needle  1 , catheter  2  and a syringe cover  7 . The syringe needle  1  has an inserting portion  11  at a front end. On the inserting portion  11  is inserted an injection needle  111 . On the syringe needle  1 , at least one fastening portion  12  is molded on one side and a ventilating filter  13  is at its rear end. The fastening portion  12  and syringe needle  1  is connected by a shank  33  (not shown in the figure). 
         [0036]    The catheter  2  has a cannula  21  with a flexible tube  22 . A inserting portion  11 ′ formed at a front of the syringe cover  7 . At least one gliding portion  72  extends at an outer rim of the syringe cover  7 , and corresponds to the fastening portion  12  of the syringe needle  1  in position and amount. On each of the gliding portions  71 , a sliding slot  72  is disposed. A deflected slant portion  74  is formed at the distal end of the sliding slot  72 . Referring to the top view of  FIG. 5 , the diameter of body of the syringe needle  1 , a 1 , is smaller than the inner diameter b 1  of the syringe cover  7  at horizontal axis. 
         [0037]    Syringe cover  7  meets with the insertion portion  11  of the syringe needle  1 , while catheter  2  meets with inserting portion  11 ′ of syringe cover  7  via the cannula  21 . Injection needle  111  enters catheter  2  through syringe cover  7 . The snug friction between the cannula  21  of catheter  2  and the inserting portion  11 ′ of the syringe cover  7  lets syringe cover  7  move with catheter  2 . Also, fastening portion  12  of syringe needle  1  moves freely along the sliding slot  72  of the syringe cover  7 . 
         [0038]    Referring to the top view of  FIG. 6   a , the diameter of body of the syringe needle  1 , a 1 , is smaller than the inner diameter b 1  of the syringe cover  7  at horizontal axis; hence, there is a gap c 1  between a 1  and b 1 . Syringe needle  1  is positioned in the center of syringe cover  7 . The syringe needle  1  is in the front position of the syringe cover  7  now. Referring to the side view of  FIG. 6   b , the outer diameter of body of syringe needle  1 , d 1 , coincides with the inner diameter of syringe cover  7  at the vertical axis, and does not allow having gap between them as illustrated B-B section. The longitudinal axis of the injection needle  111  is coaxial with the longitudinal axes of the syringe needle  1  and the syringe cover  7 . 
         [0039]    Then the injection needle  111  penetrates the skin and vein of the patient and guides the catheter  2  into the vein. At the same time, the catheter  2  moves forward. The cannula  21  of catheter  2  makes a snug friction fit over the inserting portion  11 ′ of the syringe cover  7 . If the syringe cover  7  has one hook at the frontel and the catheter  2  has a stop portion disposed on an outer rim of the cannula (not shown in the figures). The hook portion of the syringe cover  7  connects to the stop portion of the catheter  2  (not shown in the figures). Then the user can operate more reliable. When catheter  2  moves forwards into the vessel, syringe cover  7  moves forward too; in the meantime, fastening portion  12  moves backwards along the sliding slot  72  of syringe cover  7 . 
         [0040]    When fastening portion  12  enters slant portion  74 , the injection needle  111  is already inside of syringe cover  3  and at the back of inserting portion  11 ′. 
         [0041]    As shown by  FIG. 7   a , body of syringe needle  1  is not at the center of syringe cover  7  but is deflected to the right side at horizontal direction. A salient  73  is disposed either at the rear end of sliding slot  72  or on slant portion  74 . The salient  73  prevents fastening portion  12  to move forward when the fastening portion  12  enters slant portion  74 . It is very difficult for injection needle  111  to exposed outside of syringe cover  3 . In  FIG. 7   a , numeral  14  denotes the position of syringe needle  1  at sliding slot  72  without deflection; numeral  15  denotes the position of syringe needle  1  at slant position  74 , while injection needle  111  is already deflected from the center of syringe cover  7 . 
         [0042]    In the side view of  FIG. 7   b , body of syringe needle  1  is still at the center of syringe cover  7  at the vertical axis; i.e. 
         [0043]    injection needle  111  is deflected to the right side at horizontal direction and sits behind inserting portion  11 ′ of syringe cover  7 . We also can see the syringe needle  1  deflects to the left side as shown in B-B section view. 
         [0044]    Further referring to  FIG. 8 , a reception slot  75  is disposed at the rear end of slant portion  74  of syringe cover  7  to secure the syringe needle  1  in position when syringe needle  1  enters reception slot  75 . 
         [0045]    The latest design refers to  FIG. 9 , the safety catheter structure consists of a syringe needle  1 , catheter  2 , and syringe cover  5 . An injection needle  111  is disposed at the front end of syringe needle  1  and ventilating filter  13  is inserted, while a fastening portion  12  is disposed on one side of catheter  2 . A flexible tube  22  is disposed at the front end of cannula  21  of catheter  2 . An inserting portion  11 ′ is at the front end of syringe cover  5 , and a sliding slot  52  on gliding portion  51  of syringe cover  5 . 
         [0046]    Further referring to  FIG. 10 , syringe cover  5  connects via inserting portion  11 ′ with inserting portion  11  of syringe needle  1 , while catheter  2  connects via cannula  21  with inserting portion  11 ′ of syringe cover  5 . Injection needle  111  of syringe needle  1  enters catheter  2  through syringe cover  5 . Syringe cover  5  moves with catheter  2  by the snug friction between cannula  21  of catheter  2  and inserting portion  11 ′ of syringe cover  5 . Under the same process, fastening portion  12  of syringe needle  1  moves freely in the sliding slot  52  of syringe cover  5 . The top view of  FIG. 10   a  shows that the outer diameter of body of syringe needle  1 , d 1 , coincides completely with the inner diameter of syringe cover  5 , and does not having gap between them, as shown c (Enlarge view). The side view of  FIG. 10   b  shows that the diameter of body of syringe needle  1 , a 1 , is smaller than the inner diameter b 1  of syringe cover  5  at the vertical axis, making a gap c 1  between them. When it is not in use, therefore, syringe needle  1  is positioned at the front of syringe cover  5 . If the syringe cover  5  has at least one hook at the frontel and the catheter has a stop portion disposed on an outer rim of the cannula (not shown in the figures). The hook portion of the syringe cover  5  connects to the stop portion of the catheter  2 . (not shown in the figures). Then the user can operate more reliable. 
         [0047]    When catheter  2  moves forward into the vessel, syringe cover moves forward too; in the meantime, fastening portion  12  of syringe needle  1  moves backward along the sliding slot  52  of syringe cover  5 . When injection needle  111  enters syringe cover  5  and sits behind inserting portion  11 ′, catheter  2  is separated with syringe cover  5  ( FIG. 11 ). Since fastening portion  12  of syringe needle  1  is already positioned at the right rear end of sliding slot  52  of syringe cover  5 , injection needle  111  is situated in the syringe cover  5 , as shown by  FIG. 11   a . In contrast,  FIG. 11   b  shows that syringe cover  5  is vertically rotated down from its original center position, making injection needle  111  positioned at the back of inserting portion  11 ′ and tilted upwards, due to the garviy of syringe cover  5  is located at the front and the levering effect from gravity center makes syringe cover  5  rotating down; as a result, the position of syringe needle  1  rotates, and makes injection needle  111  moves forward impossibly. Preferrably, a salient  53  is positioned at the rear end of sliding slot  52  of syringe cover  5 , which would increase its safety in use when fastening portion  12  of syringe needle  1  is positioned at the back of salient  53 . In  FIG. 11   b , numeral  16  denotes the position of syringe cover  5  at original position; numeral  17  denotes the position of syringe needle  1  at the right rear end of slide slot, while signal cover  5  is already rotation down. 
         [0048]    Further referring to  FIG. 12   a , a salient  55  is positioned below fastening portion  12  of syringe needle  1 . When fastening portion  12  moves to the right rear end of sliding slot  52 , the levering effect from gravity of the syringe cover makes the syringe cover  5  rotating down. Then the user vertically pushes the fastening portion  12  to let the salient  55  into the sliding slot  12 , which would increase its safety in use, as shown by  FIG. 12   b .  FIG. 12   b  shows that syringe cover  5  is vertically rotated down from its original center position. 
         [0049]    Many changes and modifications in the above the described embodiment of the invention can, of course, be carried out without departing from the scope. Accordingly, to promote the progress in science and the useful arts, the invention will be disclosed and intended to be limited only by the scope of the appended claims.