Abstract:
An improved medical syringe enables quick operation of a handle member to position a needle and syringe barrel in selected positions to extend and withdraw a needle to provide a needle system or a needle-less system.

Description:
BACKGROUND AND SUMMARY OF THE INVENTION  
       [0001]     The syringe of the present invention has a retractable needle positionable by a handle engageable in any of a plurality of stops or notches by simple manual manipulation, whereby the syringe is convertible from a needle to a needle-less system by extending or withdrawing the needle. The needle may be extended for aspirating a solution into the syringe from a bottle or an ampoule. The solution may then be injected into a patient directly or through an intravenous port. The needle may be retracted to expose the blunt tip of the syringe for engaging a needle-less intravenous port.  
         [0002]     The syringe of the invention is versatile in other respects. Conversion from a needle system to a needle-less system or vice versa is readily accomplished by manipulating a control handle without touching the needle, thus greatly reducing the risk of accidentally sticking the operator with the needle. Removal and replacement of a needle are eliminated. The conversion from a needle system to a needle-less system and vice versa may be repeated again and again for a single patient in accordance with the patient&#39;s needs. A needle may be used repeatedly without removal from the syringe, thus eliminating the discarding of many needles, and the attendant high costs of such discarding. To dispose of the syringe or when the syringe is temporarily out of service, the needle is readily retractable into the syringe housing by operation of the handle. The foregoing advantages and convenience save substantial medical professional time in assembling and filling of syringes. The capability provided by the syringe of the invention can avoid delays and is even life-saving in some circumstances.  
         [0003]     In a preferred embodiment, the present invention comprises a syringe barrel slidable in an outer housing, a hollow needle extending forwardly from the syringe barrel and movable with the barrel to penetrate a resilient member and extend outwardly from the housing. A control handle is pivotally mounted and has means to engage any of a plurality of spaced-apart stops or notches for the selective positioning of the needle to extend it beyond the forward end of the housing or to retract the needle within the housing.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]      FIGS. 1, 2  and  3  are sectional views of a preferred embodiment of the present invention, showing the needle and other components in different positions in use in operation of the syringe of the invention;  
         [0005]      FIG. 4  is a top view of the syringe of  FIGS. 1-3 ;  
         [0006]      FIG. 5  is a sectional view taken at line  5 - 5  in  FIG. 3 ;  
         [0007]      FIG. 5A  is a sectional view taken at line  5 A- 5 A in  FIG. 4 ;  
         [0008]      FIG. 6  is a perspective view of the syringe of  FIGS. 1-3  with its needle extended;  
         [0009]      FIGS. 7, 8  and  9  are sectional views of a second embodiment of the syringe of the invention, showing components in successive positions of operation;  
         [0010]      FIG. 10  is a top view of the embodiment of the invention shown in  FIGS. 7-9 ;  
         [0011]      FIG. 11  is a sectional view taken at line  11 - 11  in  FIG. 9 ; and  
         [0012]      FIG. 12  is a perspective view of the syringe of  FIGS. 7-9 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0013]     Referring to the drawings, a preferred embodiment  10  of the present invention comprises an outer housing  12 , a syringe body or barrel  14  of generally cylindrical configuration, and a plunger  16  slidable in the syringe body  14 .  
         [0014]     A helical spring  18  is disposed between an end wall  20  of the housing and an end wall  24  of the plunger  16 . A hollow needle  22  is extensible through end wall  24  of the syringe to communicate with the interior of the syringe.  
         [0015]     A resilient seal  26  is threadedly mounted in the end wall  20 . The needle  22  extends through the resilient seal member  26  and tubular end member  28 . The needle preferably has an inclined sharp end portion to facilitate entry into a plug of a vial or an opened ampoule for aspiration of liquid, or for injection into a person.  
         [0016]     Control handle  34  is manually pivotal about a pivot  36  on a bracket secured on a forward portion of syringe barrel  14 , as shown. The handle  34  extends outwardly via an upper opening in the housing  12 , as shown. As shown in  FIGS. 5 and 5 A, a spring  38  having a coiled central portion and respective arms engaging the handle and the bracket engages the handle  34  and the bracket mounted on the syringe housing, thus to bias the handle  34  upwardly and outwardly relative to the pivot at  36 .  
         [0017]     In assembling the syringe of the invention, a foot or ridge  40  on the syringe is first positioned outwardly of housing  12 , as shown in  FIG. 1 . As assembly proceeds, foot  40  moves inside the housing  12 , as shown in  FIG. 2 , and engages a bent end portion  41  to prevent the syringe  14  from moving outwardly on housing  12 . The syringe is then movable to extend needle  22  to pierce seal  26 , as indicated in  FIG. 3 . Housing  12  is at the lower portion of undulating contour, as shown, for improved manual gripping.  
         [0018]     A rod portion  42  on the handle  34  is adapted to engage in any of the notches  44 ,  46  or  48  defined in the upper portion of the housing. In utilizing the syringe, portion  42  of the handle is first engaged in the first notch  44 . To move the handle portion to engage in the second notch  46 , it is only necessary to push the handle a short distance forward to engage the second notch  46  and cause the needle to pierce and extend through the seal member  26 . Once the handle is moved into the second notch  46 , the syringe cannot then be moved back to notch  44  because the foot  40  is retained by the end edge of the housing  12 .  
         [0019]      FIG. 3  shows the handle engaged in the third notch  48  so that needle  22  extends outwardly from the end of the housing for use in injection of medication into a person or aspiration of medication or drug from a bottle or an ampoule. In this position, the force of the compressed spring  18  is resisted by the engagement of handle rod portion  42  in the third notch  48 . The needle remains in this position until released by manual pressure on handle  34 .  
         [0020]     In utilizing the syringe, plunger  16  is axially movable outwardly by pulling on outer cap  50  of the plunger to produce suction in the syringe to draw liquid from an ampoule or bottle, etc. Urging the plunger inwardly produces pressure in the syringe as for injecting via the needle  22  or via tubing connected to patient to inject liquid into a patient, bottle or ampoule.  
         [0021]     Further, a watertight seal at needle  22  prevents liquid in the syringe from retrograde flow into housing  12  when the tip of the housing is attached to a female connector onto intravenous tubing, regardless of whether positive or negative pressure is applied to the syringe plunger with the syringe plunger pushed forward or pulled backward.  
         [0022]     A second embodiment of the present invention is illustrated in  FIGS. 7-12 . This embodiment comprises certain improvements or alternate features which differ from the embodiment of  FIGS. 1-6 . Features of this embodiment which are in common with the first embodiment are identified by the same reference numerals.  
         [0023]     Like the embodiment of  FIGS. 1-6 , the device of  FIGS. 7-12  may be used as a needle system and also as a needle-less system.  
         [0024]     The embodiment of  FIGS. 7-12  differs from that of  FIGS. 1-6  in that its upper body portion and upper features are flatter and lower and in that notches  76 ,  78  and  80  are defined differently and differently positioned, as shown. A handle  64  is pivotally mounted relative to the syringe, as in the embodiment of  FIGS. 1-6 . A hook portion  70  is pivotal by means of handle  64  to engage the hook in a selected notch  76 ,  78 , or  80 .  
         [0025]     As with the embodiment of  FIGS. 1-6 , an important feature of the invention is the provision of means whereby simply pushing on the handle  64  converts the syringe from a needle to a needle-less device. With the syringe in its forward position of  FIG. 9 , with the hook  72  disposed in the third notch  80 , the needle extends outwardly from the housing, as shown in  FIG. 9 . With the needle in its outward position, the user maintains pressure on the spring.  
         [0026]     The components remain in steady positions with needle extended until released by manual downward pressure on the handle and pushing forwardly on the handle to release the prong from the third notch  80 . The spring of the syringe urges the syringe only as far as the position shown in  FIG. 8 , wherein the needle is fully retracted into the tip of housing, as shown in  FIG. 8 .  
         [0027]     The prong  72  is stopped at a first position by engagement with the first notch  76  and only needs to be pushed a short distance forwardly to pierce the seal and engage the second notch  78 . The prong is released from the notch by pushing forward slightly and pressing downwardly on the handle  64 .  
         [0028]     It will be understood that various changes and modifications may be made from the preferred embodiments discussed above without departing from the scope of the present invention, which is established by the following claims and equivalents thereof.