Abstract:
A safety device for the needle of intravenous catheter apparatus comprising of a tip blocker which blocks the needle tip, a spring assembled in compressed state held by a disc inside the groove of the tip blocker which pushes the tip blocker downwards and a bush fitted in the needle passageway which does not allow the needle to come out of the safety device. The safety device is capable of locking inside it and covering the needle tip so that the needle of intravenous catheter apparatus can be disposed of safely.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119 of a provisional application Ser. No. 60/804,214 filed Jun. 8, 2006, which application is hereby incorporated by reference in its entirety. 
    
    
     FIELD OF INVENTION 
     The present invention relates to a safety device for the needle of an intravenous catheter apparatus. More particularly this invention relates to a safety device fitted to an intravenous catheter apparatus which covers the needle tip after use, prior to the needle being disposed of, thereby preventing accidental pricking of the used needle of the intravenous catheter apparatus by medical professionals, people in charge of disposal of hospital waste and anybody who accidentally or intentionally handles or tries to dispose of the intravenous catheter apparatus. 
     BACKGROUND OF INVENTION 
     The intravenous catheter apparatus is used to inject medicines, glucose and other nourishment, in liquid form, into the blood stream of patients during their treatment. Such intravenous catheter apparatuses are known from the prior art and permit the inlet of different media flow during the treatment of the patient. After the needle along with a flexible catheter is inserted in the vein of the patient and blood flashes in the catheter, the needle is withdrawn from the vein. The flexible catheter portion continues to remain in the vein to inject medicines, glucose and other nourishment in liquid form into the blood stream. The needle is disposed of after withdrawal from the catheter and the vein. If the used needle is not covered with some protection, it can prick anyone who comes into contact with the needle, including medical professionals and people in charge of disposal of hospital waste. Accidental pricking by used needles is very dangerous and at times even fatal if the needle has come into contact with the blood of an ill patient. Accidental pricking may spread blood borne diseases like Hepatitis B, AIDS, etc. In view of the foregoing, a safety device is essential to completely cover the tip of the needle after use and while disposing it to thereby prevent contact with the needle. 
     The prior art acknowledges the need for a needle tip guard placed upon the needle after it&#39;s been withdrawn from the catheter. For example, U.S. Pat. No. 5,135,504 uses a needle safety device in which a “retaining ring” is fitted inside the intravenous catheter apparatus and the “needle guard” slides inside the retaining ring. This device has some of the following disadvantages: 1) the retaining ring remains inside the main body during use of the apparatus which hinders flow of solutions through it, 2) there is a likelihood that guard jaws which cover the needle tip may open so as to expose the needle tip, 3) there is chance that blood on or near the needle tip may surface out of the needle guard because the needle is still exposed from the sides and because the size of the needle guard is too small with respect to the portion of the needle needing to be covered. 
     In other prior art references such as U.S. Pat. No. 6,117,108, the safety device remains inside the main body of the catheter apparatus. However, because of the miniature size of the main body there remains a strong probability of blood coming out of the safety device and infecting the persons handling the used needle. 
     OBJECTS OF INVENTION 
     A primary object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus that facilitates and ensures safe disposal of the needle of the intravenous catheter apparatus after the needle is withdrawn from the vein of a patient following cannulation. 
     Another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus in which the disadvantages of prior art are overcome. 
     Another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus, which securely locks the needle tip so that the needle may not be pushed or pulled out of the safety device. 
     A further object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus, which is big enough to cover the needle tip from all sides thereby preventing infected blood from oozing out of the safety device. 
     Yet another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus which may be fitted between a wing body and needle hub in such a way that it does not create any impediment to the function and operation of the intravenous catheter apparatus. 
     Still another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus, which is externally attached to the body of the apparatus so that no part remains inside the apparatus to affect the flow of liquid through the apparatus. 
     A further object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus, which requires only slight force to detach it from the wing body, without disturbing the position of the catheter. 
     Still another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus, which can be easily assembled and involves a simple structural configuration. 
     Another object of this invention is to propose a safety device for the needle of an intravenous catheter apparatus which is economical to produce. 
     SUMMARY OF THE INVENTION 
     The present invention consists of safety device for the needle of an intravenous catheter apparatus, which is provided between the wing housing and the needle hub of an intravenous catheter apparatus. After the needle along with the flexible catheter is inserted in vein of the patient and blood flashes in the catheter, the needle is withdrawn from the vessel holding the wing housing. The needle bug along with the needle moves out of the catheter and thereafter passes through the wing housing and reaches the safety device. As soon as the needle tip moves past the tip-blocker, the tip-blocker is forced downward, due to the pressure of the spring, in front of the needle tip. Thus, the tip blocker blocks and prevents the needle tip from moving forward in the direction of the catheter. When the needle is further withdrawn, the flaring near the tip of the needle prevents the needle from being pulled out of the safety device. In this position, the needle can neither move inward nor outward and is totally locked inside the safety device. If further force is applied in the outward direction to withdraw the needle, the safety device detaches itself from the wing housing and the needle hub assembly, such that the needle and safety device together separate from the wing assembly. The needle can now be safely disposed of as the needle tip is locked inside the safety device in such a way that it cannot be pushed or pulled out of the safety device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of an intravenous catheter apparatus. 
         FIG. 2  is a cross sectional view of the apparatus of  FIG. 1  taken along line  2 - 2 . 
         FIG. 3  is an enlarged view of section  3 - 3  of  FIG. 2 . 
         FIG. 4  is a top view of the intravenous catheter apparatus with the needle partially removed from the catheter and wing housing. 
         FIG. 4A  is a cross sectional view of the apparatus of  FIG. 4  taken along line  4 A- 4 A. 
         FIG. 5  is an enlarged view of section  5 - 5  of  FIG. 4A . 
         FIG. 5A  is an isometric view of section  5 - 5  of  FIG. 4A . 
         FIG. 6  is a top view of the intravenous catheter apparatus with the needle pulled out of the wing housing and locked in the safety device. 
         FIG. 6A  is a cross sectional view of the apparatus of  FIG. 6  taken along line  6 A- 6 A. 
         FIG. 7  is an enlarged view of section  7 - 7  of  FIG. 6A . 
         FIG. 7A  is an isometric view of section  7 - 7  of  FIG. 6A . 
         FIG. 8  is a top view of the intravenous catheter apparatus with needle along with safety device detached from the wing housing. 
         FIG. 8A  is a cross sectional view of the apparatus of  FIG. 8  taken along line  8 A- 8 A. 
         FIG. 9  is an enlarged view of section  9 - 9  of  FIG. 8A . 
         FIG. 9A  is an isometric view of section  9 - 9  of  FIG. 8A . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , an intravenous (IV) catheter apparatus  10  of the present invention is shown. It comprises of needle cover  12 , wing housing  14 , port  16  in unitary assembly with the wing housing  14  and needle hub  20 . Luer lock  22  is removably attached to wing housing  14 . The needle cover  12  covers the needle  24  (shown in  FIG. 2 ). The needle hub  20  can be detached from the wing housing  14  such that the assembly of needle  24 , needle hub  20  and luer lock  22  can be separated from the assembly of wing housing  14  and port  16 , such as shown in  FIG. 8A . 
       FIG. 2  is a cross sectional view of the IV catheter apparatus  10  which depicts a needle  24  extending from needle hub  20  through the wing housing  14  and ending at the needle tip  26  under the needle cover  12 . 
     The needle  24  is hollow and the needle tip  26  is cut diagonally. There is needle flaring  28  which increases the diameter of the needle  24  near the needle tip  26 . Surrounding the needle  24  is a catheter  30  which is attached to the wing housing  14  at the catheter base  32 . The catheter  30  is a flexible tube which is placed in the vein of a patient to provide fluids, nourishment and medicines. Wing housing  14  has a port  16  covered by port cap  18  through which fluid, nourishment or medicines are injected which travel through wing housing  14  and catheter  30  into the patient&#39;s vein. The safety device  34  is located between wing housing  14  and needle hub  20  and is aligned in the vertical plane along the plane of port cap  18  and needle hub  20 . Two lugs  36  removably hold the safety device  34  to the wing housing  14 . 
       FIG. 3  is the enlarged cross sectional view of the safety device  34  of  FIG. 2 . The needle  24  passes through the needle passageway  38  and bush  40  inside the safety device  34 . The safety device  34  has a tip blocker  42  which blocks the needle tip  26 . A spring  44  is arranged in a compressed state inside the groove  46  of the tip blocker  42  and is held in such position by a disc  48 . 
     To use the IV catheter apparatus  10  the needle cover is removed and the needle  24  along with catheter  30  is inserted into the patient&#39;s vein. Because the blood within the vein is under pressure, as soon as needle tip  26  punctures the skin and enters the vein, blood gushes up into the hollow needle  24  and through the wing housing  14  until it reaches the flash back chamber  50  shown in  FIGS. 2 ,  4 A,  6 A and  8 A. The needle  24  is then withdrawn out of the vein and the catheter  30  by pulling the needle hub  20  away from the wing housing  14 . The needle  24  passes through catheter base  32  and silicon tube  52 . 
       FIG. 4  shows the top view of the IV catheter apparatus  10  when the needle  24  is partially withdrawn form the wing housing  14 . The cross section of  FIG. 4A  shows clearly that the needle  24  has moved past the catheter  30 , the catheter base  32  and the silicon tube  52  such that the diagonal cut portion of needle tip  26  is being withdrawn toward the safety device  34 . 
       FIG. 5  is the enlarged cross sectional view of the safety device  34  of  FIG. 4 .  FIG. 5  depicts the needle  24  touching the tip blocker  42  and passing through the bush  40 . Needle flaring  28  near the tip blocker  42  is also shown. The spring  44  is shown in the compressed position. In this position, the spring  44  exerts downward pressure on the tip blocker  42 . 
       FIG. 5A  provides an isometric view of  FIG. 5  showing the parts of the wing housing  14 , namely the needle tip  26 , needle flaring  28 , tip blocker  42  and bush  40 . 
       FIG. 6A  is a cross sectional view taken along line  5 - 5  of  FIG. 6 .  FIG. 6A  shows the needle tip  26  being blocked by the tip blocker  42  preventing any forward movement of the needle tip  26  within the safety device  34 . By pulling the needle hub  20  the needle  24  and needle tip  26  moves past the tip blocker  42 ; the tip blocker  42  falls down under the pressure of compressed spring  44  and enters the needle passageway  38 , which blocks the needle passageway  38 . 
       FIG. 7  is an enlarged cross sectional view taken along line  7 - 7  of  FIG. 6A .  FIG. 7  shows how the spring  44  has moved tip blocker  42  into the needle passageway  38  thereby blocking any forward movement of the needle tip  26 . In this position, the needle tip  26  cannot move outside the wing housing  14 . The location of needle flaring  28  and position of bush  40  is fixed in such a way that when the tip blocker  42  comes down, the needle flaring  28  is inside the safety device  34  in front of the bush  40 .  FIG. 7A  shows an isometric view of the constituent parts of the safety device  34  namely, tip-blocker  42  blocking needle tip  26 , flaring  28  and bush  40 . 
       FIG. 8  shows safety device  34 , needle  24  and needle hub  20  in unitary assembly being detached from the wing housing  14 . 
       FIG. 8A  shows the safety device  34  covering the needle tip  26  separated from the wing housing  14 . After the needle tip  26  is blocked by the tip blocker  42  as described in the proceeding paragraphs, upon further withdrawal of the needle  24 , the needle flaring  28  comes in contact with the bush  40 . Since the diameter of needle  24  is increased at the needle flaring  28 , the bush  40  does not allow needle faring  28  to pass through the bush  40 . Thus, the flaring  28  on the needle  24  cannot be pulled through the bush  40 . If any further force is applied to pull the needle  24  out of the safety device  34 , it detaches the lugs  36  attached to the wing housing  14 , which detaches the safety device  34  from the wing housing  14 . 
       FIG. 9  shows the flaring  28  of the needle  24  in contact with the bush  40  on one side and tip blocker  42  blocking the needle tip  26  on the other side. Thus, the needle  24  cannot be pushed or pulled out of the safety device  34  as the needle tip  26  is locked within the safety device  34 .  FIG. 9A  shows an isometric view of the safety device  34 , namely tip blocker  42 , needle tip  26 , flaring  28 , and bush  40 . 
     The needle  24  with needle hub  20  on one end and safety device  34  on the other, as seen in  FIG. 8 , can be disposed of in a safe manner. Since the safety device  34  is made sufficiently large, it covers the needle tip  26  from all sides so that the infected needle tip  26  is not exposed from any side. 
     The bush  40  and tip-blocker  42  arrangement locks the needle tip  26  very securely so that the needle tip  26  does not accidentally slip out of the safety device  34 . 
     As best shown in  FIGS. 2 ,  3  and  8 A, the safety device  34  of the present invention is an external attachment to the IV catheter apparatus  10 , which detaches completely from the wing housing  14  after use, in such a manner that it does not affect the flow of fluids in the wing housing  14  and catheter  30 . 
     The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.