A SAFETY INTRAVENOUS CATHETER ASSEMBLY
FIELD OF THE INVENTION
This invention relates to the catheter assembly and more particularly to a safety intravenous catheter assembly to place the catheter into the human body retracting the needle safely within a protective guard reducing the likelihood of the accidental needle stickiness injuries & infections.
BACKGROUND OF THE INVENTION
Intravenous Catheter Assembly is generally used to place the catheter into the human body. In general, the purpose of such assembly is the intravenous feeding. In this process, the blood vein is first punctured with the needle passing through the catheter and the catheter is placed into the punctured vein. On the successful placement of the catheter the needle is retracted. When a catheter is inserted into a patient body for the intravenous delivery of a fluid, the disposable needle passing through the catheter cannula is utilized to make a puncture to permit entry of the tip of the cannula into the patient. The needle which is now contaminated with blood or other body fluid must be disposed of without creating a risk of infection to medical personnel which are engaged in the operation of inserting a catheter. A danger to clean up and medical waste disposal personnel continues if the used needles are not rendered harmless in some way. Caps or covers that can be mounted over the needle are not a satisfactory solution because they must be put in place and can come loose and expose the used needle. For decades, the innovation on the catheter assembly is on move. Retractable catheter assembly has been the issue of innovation, wherein mechanism of the retraction of the cannula part, keeping the catheter safe into the vein, has been the matter of prior art.
As regards prior art, several patents are under the process and granted for the cannula assembly with various structures and features. Shaw et al revealed their invention U.S. Pat. No. 6,872,193 which introduces an IV catheter introducer having a retractable needle holder and a tubular plunger that are held by a detent structure in a preferred positional relationship prior to and during insertion of the catheter. Following insertion, the plunger is pushed past the detent structure, permitting a compressed spring to force the needle holder

upwardly into the plunger. A vented end cap in the plunger permits rapid venting of air displaced during retraction of the needle holder. The needle holder includes a flash chamber that is easily viewable through a clear plastic housing. Wings are provided on the housing to facilitate one-handed operation of the device. Botich et al has US Pat No. 6436070 with the title "Catheter insertion device with retractable needle" wherein the device is operable for inserting an intravenous catheter into a patient. The device includes a needle for piercing the patient's skin and guiding the catheter into the vein of the patient. The needle is operable in two positions, an extended position, in which the needle projects forwardly from a housing, and a retracted position, in which the needle is retracted into the barrel so that the needle is enclosed by the barrel to prevent inadvertent contact with the needle after use. A needle retainer releasably retains the needle in the projecting position against the bias of a spring that biases the needle rearwardly toward the retracted position. After use, the operator displaces an actuator to release the needle. The spring then propels the needle rearwardly into the retracted position. In this way, the device is non-reusable and the needle is shielded to prevent contact with the sharpened tip of the contaminated needle. Schur et al, discusses an invention through their U.S. Pat. No. 5542930 wherein The catheter assembly revealed of the present invention includes a needle component, a catheter component mounted on the needle component in a manner that permits relative axial movement between the needle component and the catheter component, and a rotatable screw means for controlling the relative axial movement between the needle component and the catheter component and for inducing rotational movement to the catheter component. U.S. Pat. No. 5911705 of HOWELL et al discuss about Safety Intravenous Catheter Assembly includes the one step catheter advancement automatic needle retraction system of this invention includes generally hollow barrel, a needle hub which can include a flashback chamber disposed in the barrel, a secondary flashback chamber disposed in the barrel, a biasing mechanism for retracting the needle into the barrel and a clip associated with the secondary flashback chamber for engaging a catheter hub. The needle hub in conjunction with the secondary flashback chamber retains the needle in the extended position against the force of the biasing mechanism until the catheter has been advanced a certain distance from the distal end of the barrel. Gutierrez et al, revealed the U.S. Pat. No. 6814725 which converse about a I.V. catheter assembly, a

catheter with a distal needle for insertion into a blood vessel. An adapter with a self-sealing or self-closing plug is connected to the catheter, proximally of the distal needle. A proximal needle that can couple to the distal needle is in a guard tube on the other side of the plug. In use the proximal needle is pushed through the plug and into coupling engagement with the distal needle so the distal needle can be inserted into a blood vessel. The coupled needles are then withdrawn and shielded in the guard tube. The guard tube is then disconnected from the adapter and the adapter can be used to discharge blood from, or supply fluid to the blood vessel.
Many more prior arts are known which also can be discussed. Pressly, Sr. et al revealed their invention U.S. Pat. No. 6942652 wherein Retractable I-V catheter placement device is given comprising an intravenous catheter placement device having a hollow body and a nose on one end of the hollow body. Chang et al has US Pat No. 6322537 with the title Safety intravenous catheter, wherein a medical IV catheter is described. Bogert et al, discusses an invention through their U.S. Pat. No. 5,99, 310 wherein I.V. catheter assembly with an automatic cannula tip guard is given. U.S. Pat. No. 5573510 of ISAACSON et al talks about Safety Intravenous Catheter Assembly with automatically retractable needle. Lather, et at introduced U.S. Pat. No. 4,762,516, which discusses about the assembly of Needle Catheter Protector.
On studying the above inventions, it has been observed that the cannulation by the stated assemblies of the patents is indeed done. However, we observe that some draw backs have been monitored which need to be overcome. The complicated structures, large numbers of components make the existing art expensive. Also, the process of manufacturing becomes lengthy increasing the manufacturing cost. So there are still requirements of one catheter assembly which should be simple in manufacturing & use also. Additionally, it should have features which can give more safe protection to the patients during and after retraction the cannula housing. Therefore, prior arts have scope of improvement from the point of view of the innovation. By overcoming the drawbacks, the present invention is provided which may be useful in the arena of catheter assemblies.

SUMMARY OF THE INVENTION
The present invention is directed to a safety intravenous catheter assembly for the simple, successful and safe cannulation. Therefore it is thus an object of this invention to provide an intravenous catheter placement assembly and system which minimizes the likelihood of accidental needle stickiness injuries. It is further object of this invention to provide such an intravenous catheter placement device which, after utilization with a patient, captures, encapsulates, and isolates the used needle so as to render such needle harmless. In the present invention, the said assembly is provided consisting a catheter unit and housing. The catheter unit is attached at its rear end to the front end of housing. The housing consists the cannula unit which moves inside a hollow body elongatedly. There is provided a slidable means which is movable slidably over the outer surface of hollow body and attachably make a motion with the cannula unit. To make the slidable means attachably move with the cannula unit, the slidable means is attached with the cannula unit through a connecting tab. The cannula unit, connecting tab & slidable means associatedly form a retractable means which moves along the length of hollow body. This tab is movable within a slot made along through the length of the hollow body. The connecting tab that is rectangular in shape is attached at its one end to the inner side of slidable means and at other end to the outer side of cannula hub of cannula unit. This unit of all three members is fitted with the hollow body in the way so that the cannula unit travels inside the housing and slidable means travels over the length of hollow body with the help of a slot designed along the length of hollow body so as to make the connecting tab capable of traveling within the said slot. Thus the connecting tab which attached slidable means & cannula unit to form a single unit of all three members, function with both members as movable member. As the slidable means moves forward at the outer surface of the hollow body along its length, the cannula also moves forward protruding its distal tip from the front side of the hollow body. The slidable means has a pair of locking tabs formed in rectangular shaped slots which can be fitted with a pair of wings designed at the rear side of hollow body. When the slidable means moves backwardly, the pair of locking tabs designed therein is fitted with the pair of wings designed at the rear side of hollow body which form a locking means as a result the slidable means locks. The hollow body has a nose mounted at its front end wherein the cannula through a passageway of hollow body protrudes at the

nose boot. The cannula may therefore pass through the passageway of the hollow body, nose, nose boot, catheter hub and inside the catheter shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plan view of intravenous catheter assembly, thus illustrating the preferred embodiment of our invention.
FIG. 1A shows the front cross sectional view of intravenous catheter assembly.
FIG. 2 shows a longitudinal cross-sectional view of intravenous catheter assembly.
FIG. 3 shows the cross sectional view of intravenous catheter assembly on the line of F-F of FIG. 2.
FIG. 4 shows the cross sectional view of barrel/hollow body of intravenous catheter assembly on the line of L-L of FIG. 5.
FIG. 4A shows the cross sectional view of barrel/hollow body of intravenous catheter assembly on the line of K-K of FIG. 5.
FIG. 5 shows a front longitudinal cross-sectional view showing slot of barrel/hollow body of intravenous catheter assembly.
FIG. 6 shows a side longitudinal cross-sectional through the nose of barrel/hollow body of intravenous catheter assembly.
FIG. 7 shows a rear longitudinal cross-sectional of barrel/hollow body of intravenous catheter assembly.
FIG. 8 shows a front longitudinal cross-sectional view of cannula unit of intravenous catheter assembly.
FIG. 9 shows a rear longitudinal cross-sectional view of cannula unit of intravenous catheter assembly.
FIG. 10 shows the cross sectional view of cannula unit of intravenous catheter assembly on the line of M-M of FIG. 8.
FIG. 11 shows a rear longitudinal cross-sectional view of slidable means of cannula unit.
FIG. 12 shows the cross sectional view of slidable means of cannula unit on the line of L-L of FIG. 11.

FIG. 13 shows the cross sectional view of catheter unit of intravenous catheter assembly on the line of E-E of FIG. 14.
FIG. 13A shows the cross sectional view of catheter unit of intravenous catheter assembly of FIG. 14.
FIG. 14 shows the longitudinal cross-sectional view of catheter unit of intravenous catheter assembly.
FIG. 15 shows the longitudinal cross-sectional view of catheter of intravenous catheter assembly.
FIG. 16 shows the longitudinal cross-sectional view of first stage opening of intravenous catheter assembly.
FIG. 17 shows the longitudinal cross-sectional view of the portion A of FIG. 16.
FIG. 18 shows the longitudinal cross-sectional view of the portion F of FIG. 16.
FIG. 19 shows the longitudinal cross-sectional view of second stage opening of intravenous catheter assembly.
FIG. 20 shows the cross-sectional view of second stage opening of intravenous catheter assembly on the line of G-G of FIG. 19.
FIG. 21 shows the cross-sectional view of second stage opening of intravenous catheter assembly on the line of G-G of FIG. 19 more elaborately.
FIG. 22 shows the longitudinal cross-sectional view of second stage opening of intravenous catheter assembly of the portion A of FIG. 19.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 is a plan view of intravenous catheter assembly & Fig 2 is a longitudinal cross-sectional view of intravenous catheter assembly as per the present invention. Catheter assembly is assembled with a catheter unit X1 & housing X2. The catheter unit X1 is attached through its rear end to the front end of the housing X2. The catheter unit X1 is designed with catheter shaft 3, catheter hub 4 & catheter head 5. Catheter shaft 3 fitted into the catheter hub 4 which is associatedly fitted into catheter head 5. The catheter is covered by a lid 1 for the support purpose from any external hit. However, the housing X2 is designed by the hollow body or barrel 9 and a retractable

means. Retractable means which is made of cannula unit, connecting tab and a slidable means 7 moves along the length of hollow body 9. While moving along the length of hollow body 9, the slidable means 7 remains at the outer surface of the hollow body 9 and cannula unit designed with cannula 2 and cannula hub 8 remains inside the hollow body 9. Figs 3 is the cross sectional view of the housing at the point F-F of Figs 2 which show the hollow body 9, slidable means 7 and cannula 2 in its normal state of non use. Figs 4-12 describe the structure of housing X2 whereas Figs 13-15 describe the structure of catheter unit XI in details.
In the housing unit of catheter assembly, the retractable means travel forwardly & backwardly along the length of hollow body/barrel 9. Both parts, slidable means 7 & cannula unit of retractable means travel along the length of hollow body 9 over its outer surface and inside the body respectively. When the cannula unit advances with the help of slidable means 7, the distal point of the cannula 2 protrudes from the front end of nose 6 of hollow body 9, which further inserts inside the catheter shaft 3. Figs 4-7 show the hollow body 9 of housing X2 from various angles. The hollow body 9 is made of a cylindrical or tubular shape (see fig 5), which has its similar diameter from the line L-L to K-K. At the front round surface of the hollow body, a slot is designed which has same width along the line H-H (see fig 7). There is a pair of wings 10 formed at the rear end of the hollow body 9 and at the same end the hollow body 9 is closed with a round plate shaped cap 11. On the other hand, the hollow body 9 has a nose 6 fixedly fitted at its front end. The nose 6 is formed of two parts, one is rear part which is a round plate shaped and another part is front part which is a small tubular structure. The round shaped plate structure, which has its diameter similar to the diameter of hollow body 9, is fitted at the front end of hollow body 9 in the manner so that the front circumference of the hollow body 9 and circumference of one surface of said plate appear in same circle. At another surface of round shaped plate, the small tubular structure with a hole in its centre of diameter is adhered. The holes of round shaped plate and small tubular structure form a straight passage with passage of hollow body 9. The nose 6 can be prepared with this method or any other appropriate method to obtain the similar structure. Alternatively, the round shaped plate can be in any other design including rectangular shaped. At the front end, the hollow body has an extension, in the form of rectangular shaped plate, at its round surface as shown in fig 4 &

Fig 6. This extension is useful in pulling back the retraction means. As part of manufacturing process, the retractable means (shown in fig 8-12) is fitted along through the hollow body 9. Retractable means formed of slidable means 7, connecting tab and cannula unit. In the cannula unit, the stainless steel cannula 2 which has its distal tip insertable into the human body or vein fitted at its rear end insertably into the cannula hub 8 at its front end. The cannula unit occupies the holiow body 9 and can move in both sides along the length of hollow body 9with the help of sliding means which is slidably fitted on the outer surface of hollow body 9. As shown in Figs 8 & 9, the slidable means 7 is a half cylindrical structure which slidably and movably fitted at the outer surface of the hollow body 9 and connected with the cannula unit through a connecting tab as shown in Fig 10 & 12. As shown in Fig 10 & 12, the "C" shaped sliding means 7 move over the hollow body 9 and round shaped cannula hub 8 as shown in middle of "C" shaped slidable means 7 freely moves inside the hollow body 9 with the help of connecting tab. This connecting tab move along with sliding means 7 and cannula hub 8 within the elongated slot made on the hollow body 9. The slidable means 7 moves along the length of hollow body 9 forwardly and backwardly. When it moves forwardly the cannula 2 through its distal tip protrudes through the hole of nose 6 and insert into the catheter through its rear end across the catheter shaft 7. When the front end of the slidable means 7 touches the nose 6, at the same time cannula 2 travels inside the catheter shaft 3 insertably and cross the whole length of the catheter shaft 3 through its distal tip. When moves backwardly the slidable means 7 cross the whole length of hollow body 9 and touches wings 10 made at the rear end of hollow body 9. The slidable means 7 has a pairs of locking tabs designed inside rectangular shaped slots (Fig 11 & 12). Fig 12 shows the pair of locking tabs extending inside the C shaped sliding means 7 & a single connecting tab connecting C shaped slidable means 7 and round shaped cannula hub 8. When the slidable means backwardly cross entire length of the hollow body 9 the locking tabs of slidable means comes into the contact with the pair of wings 10 to form a locking means. On being locked, the slidable means 7 don't move forward and at the same time the cannula 2 leave completely the catheter and remains into the hollow body 9. At the stage of locking, the catheter unit may be detached freely. The catheter unit (shown in Fig 13-15) is formed with catheter shaft 3, catheter hub 4 & catheter head 5. In normal course the catheter shaft 3 is prepared by Poly Tetra Flouro Ethylene. As a part of

manufacturing, the catheter shaft 3 through its proximal end is affixed at the catheter hub 4, which is then mounted into the catheter head 5. The catheter head 5, which has the V shaped cavity is fittedly attached at the nose of the hollow body and form a single line passageway with the cannula and hollow body.
Fig 1 shows the intravenous catheter assembly in its assembled ready-to- use condition. At the time of use, the lid 1 of the assembly is removed and the assembly is held in one hand within the fingers. The cannula 2 having catheter shaft 3 over its shaft is inserted into the human vein. On puncturing the vein, the cannula 2 is retracted through the help of retractable means by taking the slidable means pushingly back. This stage is the first stage opening of intravenous catheter assembly (see fig 16). On taking back completely, the sliding means 7 locks through its locking tab into the pair of wings 10 leaving the catheter completely free of cannula 2. Fig 17 shows the cannula tip free from the catheter and Fig 18 shows the slidable means locks in the locking wings 10. In the first opening stage, the catheter gets free from the cannula 2 and cannula rests completely inside the hollow body 9. As a result the blood contents attained by the cannula or needle 2 lock inside the hollow body 9. Fig 19 -22 demonstrate the second opening stage of intravenous catheter assembly. In this stage the catheter unit is left inside the vein of human body for the intravenous activities and the housing unit is removed in locked form. The remarkable point of the invention is this that after removing the housing unit of assembly it can be disposed safely leaving no chance of causing infection to anybody.

Claims
1. A safety intravenous catheter assembly comprising:
a hollow body, the said hollow is cylindrical in shape and has a nose at its front end and wings at the rear end and a elongated slot along the length of hollow body ; and
a retractable means includes a slidable means, connecting tab and cannula unit, wherein the slidable means is half cylindrical in shape and connecting tab is a rectangular shaped structure which connect the slidable means and cannula hub of cannula unit.
2. The safety intravenous catheter assembly as claimed in claim 1, wherein a hollow body has a tubular structure with the same diameter from front to rear end.
3. The safety intravenous catheter assembly as claimed in claim 1, wherein the elongated slot made on the hollow has a similar width along through its length so that the connecting tab move within this slot freely along its length.
4. The safety intravenous catheter assembly as claimed in claim 1, wherein nose has its front part and rear part, the rear part is plat shaped structure and front part is a tubular structure.
5. The safety intravenous catheter assembly as claimed in claim 4, wherein the circumference of the rear part of the nose is similar to the front circumference of the hollow body.
6. The safety intravenous catheter assembly as claimed in claim 1, wherein the hollow body is closed at the rear end through a closing means and further includes a pair of wings at its rear end.
7. The safety intravenous catheter assembly as claimed in claim 1, wherein the sliding means of retractable means includes a pair of locking tabs designed in a rectangular shaped slot.
8. The safety intravenous catheter assembly as claimed in claim 1, wherein the connecting
tab is connecting at its one end to the inside surface of the slidable means and at
another end to the outer surface of cannula hub of cannula unit to form a single
movable means.
9. The safety intravenous catheter assembly as claimed in claim 4, wherein the rear part of
nose can be round in shape, rectangular and in any other shape.
10. The safety intravenous catheter assembly as claimed in claim 4, wherein the rear part of
nose has a rectangular shaped extension at its round surface.
11. The safety intravenous catheter assembly as claimed in claim 1, wherein the hollow body includes an extension in the form of rectangular shaped plate at the front round surface of hollow body.