Patent Document

FIELD OF THE INVENTION 
     The present invention relates generally to the art of fully automated retractable safety syringes and more particularly to needle protection assemblies or shielding devices for syringes in order to reduce the likelihood of unintentional puncture of human beings and animals. 
     RELATED U.S. PATENT 
     The present invention is an improvement over my U.S. Pat. No. 5,938,644 entitled “Needle Protection Holder”, which issued Aug. 17, 1999. Specifically, the improvements are directed to the thumb latch and to the washer construction equipped with a Luer-Lock, Luer-slip male and female attachment that are standardized by the International Standards Organization and by the American Standards National Institute to fit all Luer-Lock and Luer-slip tipped syringes thereby turning the products into fully automated retractable safety syringes. 
     DESCRIPTION OF THE PRIOR ART 
     The spread of Acquired Immune Deficiency Syndrome or AIDS in the 1980&#39;s has greatly increased the concern of health care providers over the spread of communicable diseases through accidental needle pricks or punctures. Health care personnel including nurses, doctors and other providers accidentally prick themselves with needles on an average of two or more times a year. With the increase in AIDS, the chance of a health care provider being pricked by an AIDS contaminated needle over a period of years has become quite high and of great concern not only to health care personnel but also to government officials. In addition, other severe but less deadly diseases are known, such as hepatitis, which are transmitted through contaminated needle pricks or punctures. Such punctures occur in many ways, such as a nurse tripping while carrying a used and exposed needle or even while trying to cap a used needle. 
     Consequently, a greater need has developed for shielding devices or protection devices for needles of syringes such that the shielding devices are effective, easy to use and require only minor modifications to allow use with conventional types of syringes of the disposable and non-disposable types. Numerous devices have been developed to reduce the risk of accidental needle pricks. 
     Many of these devices include a cylindrical sheath secured to the syringe which may be telescopically advanced and retracted to enclose and expose the needle of the syringe. The currently available shielding devices that provide a cylindrical sheath to telescopically encircle the needle of a syringe suffer several deficiencies or shortcomings. Many of the existing devices require an operator such as a doctor, nurse or technician to use both hands to position the protection sheath in encircling relation with the syringe needle thereby increasing the likelihood of accidental needle pricks. Thus, when the user reaches with one hand to extend the sheath of the syringe, the medical attendant accidentally sticks the free hand through carelessness, being bumped or the like. 
     In many of the existing devices, the protective sheaths cannot be locked in encircling relationship with the syringe needle possibly resulting in accidental needle pricks if a compressed force is inadvertently applied to the protective sheath of the syringe. In other existing devices, the protective sheath permanently locks in protective relation with the syringe needle when advanced thereto preventing immediate protection of the syringe needle where the syringe must be used more than once for a given procedure. Existing sheathing devices also tend to require major modifications to existing syringes or greatly interfere with the normal use of the syringe. 
     SUMMARY OF THE INVENTION 
     It is a feature of the present invention to provide a novel needle protection holder or assembly for various types of syringes which minimizes the likelihood of accidental puncture. 
     Another feature of the present invention is to provide a needle protection holder for a syringe which, after utilization, isolates the used needle within the holder so as to render such needle harmless. 
     Still another feature of the present invention is to provide a needle protection holder or assembly for a syringe which is operable utilizing only one hand thereby permitting the other hand of the medical technician to be used for other purposes. 
     A still further feature of the present invention is to provide a needle protection holder or assembly for a syringe which includes a spring which is compressed during the injection of the fluid in the syringe into the patient whereafter the compressed spring is released which is effective to retract into the interior of the holder the needle to prevent its reuse. 
     Still another feather of the present invention is to provide a needle protection holder which is adaptable to various types of syringes including standard syringes and Luer Lock syringes, which is economical to manufacture and is efficient to use while preventing accidental punctures of humans and animals. 
     These as well as other features are accomplished by providing a device that encloses a syringe and needle within a tubular shell after the needle has been used. Its intended purpose is to remove the needle attached to a syringe from a patient, both human and animal, thereby containing the needle safely within its casing or housing. The needle protection holder disallows the exchange of bodily fluids caused by needle sticks or punctures. Such punctures can result in severe illness including death and such risk can be deterred by using the present invention. 
     A further feature of the present invention is that the needle protection holder or syringe retractor assembly can be manufactured in different sizes to fit virtually any Luer Lock, Luer-slip male and female attachments or regular point syringes on the market. Thus, the present invention will permit hospitals and clinics to select any standard brand of syringe to use with the needle protection holder of the present invention. A medical institution can use the needle protection holder along with its own brands of standard syringes, thereby preserving the institution&#39;s ability to meet financial goals while providing employees with a safe environment and peace of mind knowing that accidental punctures have been greatly diminished or eliminated. 
     While the needle protection holder or syringe retractor of the present invention is intended for single usage, a medical technician could, if needed, unlock its mechanism and reuse the same syringe. This could prove useful in situations where multiple usage of a syringe is required such as in the administration of numbing or pain killing drugs to the same patient. This needle protection holder or device appears to be the first device to fit and lock onto a Luer Lock and onto a regular point syringe. A feature of the present invention is the provision of an attachment washer which is designed to connect a syringe and a needle utilizing the same method currently used to connect a syringe and a needle together. The Luer Lock and regular point syringe are two of the most common syringes currently used by hospitals and by veterinary clinics and would, therefore, provide a great deal of risk management protection. Thus, the needle protection holder or syringe retractor or device has been designed so that the medical technician can manipulate it with only one hand thereby freeing up the technicians other hand for other vital medical operations. It is well known that time can make the difference between life and death in many medical situations and can also effect the efficiency in which the medical technician cares for his or her own safety. With the present invention, virtually no time is lost in preparing the device for use; assembly takes only a matter of a few seconds to complete. Once the technician has administered the injection, the touch of the spring biased latch causes the needle to retract safely within the constraints of the tubular housing. 
     Another feature of the present invention is to provide a needle protection holder with a novel thumb latch mounted on the cylinder, a pair of spaced apart stop pedestals are provided on the cylinder and are provided with axles below the stop pedestals. The thumb latch has an integral lip opposite the longitudinal axis of the cylinder and a pair of spaced apart arms rotatably carried by the axles whereby when the latch is rotated in one direction about the axles towards the longitudinal axis it causes the lip to engage the syringe contained in the cylinder and thereby retain and latch the syringe in place. 
     Still another feature of the present invention is to provide a needle protection holder wherein the thumb latch when rotated in the opposite direction away from the longitudinal axis about the axles cause the lip to disengage from the syringe and the thumb latch to move away from the cylinder in an amount limited by the engagement of the thumb latch with the stop pedestals. 
     A further feature of the present invention is to provide a needle protection holder wherein the thumb latch has a curved surface for a person&#39;s thumb when operating the latch, with the lip being an integral part of the latch and being inclined downwardly towards the open end of the cylinder. 
     A still further feature of the present invention is to provide a needle protection holder wherein the thumb latch is provided with an integral downwardly extending spring located between the spaced apart arms, with the spring being engageable with the exterior surface of the cylinder wall and providing pressure on the thumb latch so that the locking of the syringe in the down position can take place. 
     A still further feature of the present invention is to provide a needle protection holder wherein the thumb latch including the arms, lip and spring are molded as an integral unit from a plastic material. 
     Another feature of the present invention is to provide a needle protection holder where the stop pedestals are formed out of the walls of the cylinder holding the axles. 
     Still another feature of the present invention is to provide a needle protection holder wherein the spring is flat and of generally rectangular cross-section and glides on the exterior surface of the cylinder. 
     A further feature of the present invention is to provide a needle protection holder wherein the axles are aligned directly under the lip of the thumb latch. 
     A still further feature of the present invention is to provide a needle protection holder wherein the arms of the thumb latch are provided with openings so that the arms when pressure is applied to the arms, the openings receive the axles. 
     A still further feature of the present invention is to provide a needle protection holder wherein the inner edges of the arms are beveled to remove materials and thereby facilitate the mounting of the thumb latch on the axles. 
     Another feature of the present invention is to provide a needle protection holder for a fully automated retractable safety syringe, with the holder containing a generally cylindrical washer with four circumferentially spaced apart arms provided on their outer unattached ends with radially outwardly extending protrusions or buttons. The protrusions have matching elongated channels and matching elongated openings or slots on the interior surface of the cylinder extending through the wall of the cylinder, with the protrusions, channels and elongated openings cooperating to maintain the orientation of the washer in the cylinder. 
     Still another feature of the present invention is to provide a needle protection holder wherein the arms of the washer are provided with first and second pairs of arms, each arm being integrally connected on one end of the washer, with the first pair of arms being located 180° apart, with the second pair of arms being located 180° apart, with the cylinder wall having a pair of elongated openings for receiving the outwardly extending protrusions thereby preventing the movement of the washer towards one end of the cylinder and preventing the washer and the syringe and needle from existing the cylinder when an upward thrust is applied to the washer. 
     A further feature of the present invention is to provide a needle protection holder wherein each of the protrusions or buttons has a top surface, a pair of side surfaces, an outer surface and a bottom surface, with the top surface being angled upwardly to facilitate the movement of the protrusion into the corresponding elongated opening in the cylinder and thereby catch and hold the washer in position in the elongated openings. 
     A still further feature of the present invention is to provide a needle protection holder wherein the bottom surface is inclined upwardly to permit the washer to move towards the bottom wall of the cylinder without catching in the elongated openings. 
     Another feature of the present invention is to provide a needle protection holder wherein the elongated openings are offset from the center and the protrusions or buttons are offset from the center line of the first pair of arms. 
     Still another feature of the present invention is to provide a needle protection holder wherein each of the arms of the second pair has a center line, with the second arms having outwardly projecting protrusions or buttons which are symmetrically arranged on the center lines thereof, with the cylinder wall between the ends having a second pair of elongated openings for receiving the protrusions or buttons of the second arms for stopping downward movement and unlocking of the washer when required so that downward movement of the washer can occur. 
     Still another feature of the present invention is to provide a needle protection holder wherein the second pair of elongated openings in the cylinder wall are in the form of T-shaped slots, with the protrusions or buttons of the second pair of arms when received in the T-shaped slots preventing the washer from being pushed downwardly into the bottom of the cylinder. 
     A further feature of the present invention is to provide a needle protection holder wherein the cylinder is provided with a pair of elongated flexible release arms which overly the T-shaped slots, the release arms when inward pressure is applied thereto engaging the protrusions or buttons of the second pair of arms to disengage the protrusions from the T-shaped slots thereby permitting manual pressure to be applied to the syringe to move the washer, syringe and needle downwardly into the bottom of the cylinder, where the syringe is locked in the down position by the thumb latch. 
     Other advantages and features of the present invention shall become apparent from the following detailed description of the preferred embodiment thereof, when taken in conjunction with the drawings wherein like reference characters refer to corresponding parts in the several views. 
     The drawings constitute a part of this specification and include an exemplary embodiment of the present invention and illustrate various features thereof. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of the syringe and the needle protection holder with the syringe plunger and the needle covered by a safety cap in a latched position ready for use. 
     FIG. 2 is a fragmentary perspective view of the needle protection holder with parts broken away. 
     FIG. 3 is a fragmentary perspective view of the needle protection holder with parts broken away and showing the structure for mounting the thumb latch on the axles of the cylinder. 
     FIG. 4 is an elevational side view of the needle protection holder and syringe, with parts broken away and in a locked position ready for use. 
     FIG. 5 is a side elevation of the needle protection holder and syringe looking in the direction of arrow  5  of FIG.  4 . 
     FIG. 6 is a top view of the needle protection holder and syringe of FIG.  4 . 
     FIG. 7 is a bottom view of the needle protection holder and syringe of FIG.  4 . 
     FIG. 8 is a cross sectional view taken on the line  8 — 8  of FIG.  6  and showing the syringe in a latched position. 
     FIG. 9 is a cross sectional view taken on the line  9 — 9  of FIG.  8  and showing the syringe in a latched position. 
     FIG. 10 is a cross sectional view of the needle protection holder and syringe in an unlatched position, with the needle contained within the cylinder. 
     FIG. 11 is a cross sectional view taken on the line  11 — 11  of FIG.  10 . 
     FIG. 12 is a cross sectional view taken on the line  12 — 12  of FIG.  10 . 
     FIG. 13 is a perspective view of the thumb latch illustrating the integral lip, spaced apart arms and integral spring. 
     FIG. 14 is another perspective view of the thumb latch taken from a different direction and illustrating the curved thumb rest and other side thereof. 
     FIG. 15 is a perspective view of the generally cylindrical internal washer, arms, protrusions and the Luer Lock couplings. 
     FIG. 16 is another perspective view of the washer assembly of FIG. 15 looking downwardly on the assembly and illustrating the relationship between the spaced apart arms, protrusions and the Luer Lock couplings. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, the needle protection holder is designated by the numeral  10  and is designed to be interposed between a hypodermic syringe  12  and a needle  14  (FIGS. 8-11 inclusive). The holder  10  comprises an elongated cylinder, tube or main housing unit  16  having an elongated extending axis  18 . The holder is made from a clear plastic material. 
     The syringe  12  is a conventional disposable or nondisposable hypodermic syringe having a Luer Lock coupling  20  and a needle hub  22  at the needle end of the syringe housing, cylinder or barrel  24 . The barrel  24  of the syringe  12  at the other end is open and receives a conventional plunger  26  having a thumb rest  28  at one end and a piston-like element  30  attached thereto at the other end. The plunger  26  moves up and down within the syringe barrel  24  when pressure is applied to the thumb rest  28  of the plunger and to thereby dispense fluid from the syringe  12  through the needle  14 . The open end of the barrel  24  is provided with a finger flange  32 . The outer surface  34  of the barrel  24  is provided with suitable graduations  36  which can be viewed through the clear plastic holder  10  in FIGS. 1 and 4. Such graduations are used on the syringe  12  to indicate the capacity of the medication to be administered. 
     The needle protection holder  10 , excluding the hypodermic syringe  12  and needle  14 , includes the main housing, tube or cylinder  16 , and a compression spring  38  shown in an expanded or extended position in FIGS. 10 and 11 and in a compressed position in FIGS. 8 and 9. The needle protection holder  10  further includes an improved unitary washer or washer assembly  40  and a unique thumb latch  42 . 
     The upper end of the elongated cylinder  16  is open and is enlarged to provide an oval-like entrance  44  to the cylinder or tube  16 . The enlarged oval entrance  44  has various curves and/or flat surfaces  46  terminating at the entrance by the ring-like rim  48 . The other end of the cylinder  16  has an inwardly turned flange providing a bottom wall  50 . The bottom wall  50  has an opening  52  through which the needle  14  and the needle cap  54  may extend as illustrated in FIGS. 8 and 9. The bottom wall  50  and the interior thereof provides a spring seat  56  for the compression spring  38  as illustrated in FIGS. 8 and 9. 
     The oval surface or wall  46  provided at the enlarged mouth of the cylinder  16  has a pair of stop pedestals  60  (FIGS. 3 and 10) which are formed out or struck out of the walls of the oval wall  46 . The purpose of the stop pedestals  60  as will subsequently appear is to prevent the thumb latch  42  from traveling too far outwardly away from the longitudinal axis  18  of the cylinder  16 . The exterior of the oval wall  46  is provided with a pair of axles  62 . The axles  62  are located generally directly below the stop pedestals  60 . The stop pedestals  60  are formed out of the walls  46  of the cylinder  16  to which the axles  62  are connected. 
     The thumb latch  42  has an integral body  64  made from a plastic material. The top surface of the thumb latch  42  is provided with a curved area  66  upon which the thumb of the user rests when operating the syringe  12 . The thumb latch  42  further includes a pair of integral laterally spaced apart arms  68 , the outer or free ends of the arms  68  each being provided with an opening  70  for receiving an axle  62 . The one-piece plastic molding or thumb latch  42  further includes a downwardly extending rim or lip  72  that causes the latch  42  to catch and stop when the latch  42  stops. The lip is molded into the underside of the thumb latch  42 . 
     The unitary thumb latch  42  includes a resistance spring  74  that is built into the thumb latch  42 . The spring  74  is elongated and of generally rectangular cross-section. The plastic material used to make the thumb latch  42  is taken from the group of plastic including polypropylene and Nylon. The underside of the oval-like entrance  44  to the cylinder  16  is provided with a finger hold or surface  76  which a person grips with the fingers when applying thumb pressure to the thumb rest  28  of the plunger  26 . 
     With respect to the use and functioning of the novel thumb latch  42 , the stop pedestals  60  which are struck out from the walls of the cylinder  16  (FIG. 3) are provided to provide pivot points, elements or axles  62 . One axle or pivot point  62  is located below each of the stop pedestals  60 . This feature ensures that the built-in spring  74  of the thumb latch  42  does not extend past the points where the finger rest or surface  76  begins as shown in FIG.  8 . Specifically, the resistance spring  74  which guides smoothly on the surface  46  adjacent the entrance to the cylinder  16  applies pressure thereto (FIG. 10) as the thumb latch  42  travels away from the longitudinal axis  18  of the cylinder  16 . At such time the thumb latch  42 , specifically the lip  72 , engages the stop pedestals  60  as shown in FIG. 10 thereby preventing the thumb latch from rotating further away from the center axis  18 . The spring  74  assists in stabilizing the lateral movement of the thumb latch  42  about the hinge or pivot points or axles  62 . As mentioned previously, the resistance spring  74  when the thumb latch  42  is moved in the opposite direction towards the longitudinal axis  18  of the cylinder  16  provides pressure on the thumb latch  42  so that the locking of the syringe  12  in the downward position can take place as viewed in FIGS. 1,  4  and  8 . 
     Specifically, the pivot points or axles  62  protrude outwardly from the main cylinder or housing  16  at a 90° angle from the position of the thumb latch  42 . Such pivot points or axles  62  are located near the center axis  18  of the cylinder  16  and are aligned or located directly under the holding lip  72  of the thumb latch  42  as illustrated in FIG.  1 . The purpose of the relationship between the axles or pivot  62  and the lip  72  of the thumb latch  42  is to maximize the holding ability of the thumb latch  42  when upward pressure is applied to it by the compression spring  38  of the hypodermic syringe  12  when located in the locked or down position shown in FIGS. 1,  8  and  9 . 
     To attach the thumb latch  42  to the main cylinder housing  16 , pressure is merely applied to the arms  68  of the thumb latch  42  with the result that the arms  68  snap onto the axles  62  by means of the corresponding holes or openings  70  provided in the arms. The pair of spaced apart arms  68  of the thumb latch  42  have the ends adjacent the openings  70  beveled at the inner edges to facilitate the mounting of the arms and latch  42  on the axles  62 . The openings or holes  70  provided in the arms  68  create points at which the thumb latch  42  can pivot back and forth or up and down, with the downwardly direction limited by the engagement of the lip  72  with the stop pedestals  60  (FIG. 10) as previously described. 
     The improved and novel washer assembly  40  as best illustrated in FIGS. 15 and 16 is of generally cylindrical configuration and is telescopically moveable within the cylinder  16  along the longitudinal axis  18 . The washer  40  has a unitary body  78 , first side  80  and a second side  82 . A centrally located passage  84  of varying diameter extends through the washer body  78  between the first and second sides  80  and  82 . The washer assembly  40  includes a first coupling means  86  through which the centrally located passage  84  extends. The coupling  86  is in the form of a Luer Lock type coupling which is standardized by the International Standards Organization and by the American Standards National Institute to fit all type Luer-Lock and Luer-slip tip syringes. The passage  84  may be non-threaded in accordance with the aforementioned standards or threaded to fit certain other types of syringes. 
     The washer  40  further includes a second coupling means  88  in the form of a Luer Lock type coupling with the internal passage  84  also extending therethrough. This passage  84  as mentioned previously is aligned with the passage in the first coupling  86 . The passage  84  in the second coupling  88  of the Luer Lock construction is non-threaded although in certain cases it may be threaded to fit other types of needles. Both couplings  86  and  88  are Luer Lock couplings in accordance with the aforementioned standards. The second coupling  88  is designed to carry the needle  14  as best illustrated in FIGS. 8-11 inclusive. 
     The cylinder  16  is provided with two pairs of channels  85 , which are approximately 90° apart on the interior surface  87  thereof. Each channel  85  is formed or grooved into the interior surface  87  of the cylinder  16  as best illustrated in FIGS. 8-11. The channels  85  extend from one end of the cylinder  16  to near the other end. The purpose of the channels  85  is to provide a guide or guide means between the cylinder  16  and the washer  40  for maintaining the orientation of the washer  40  and the cylinder  16  as best illustrated in FIGS. 9-11 inclusive as will be subsequently described. 
     The washer assembly  40  further includes a first pair of arms  90  and a second pair of arms  92 . The arms of each pair of arms are located 180° apart as best illustrated in FIG.  16 . An arm of one pair of arms is located 90° from the arms of the other pair of arms as best shown in FIG.  16 . 
     The arms  90  of the first pair are integrally attached to the washer body  78  at the lower ends thereof  96 . The upper ends  98  of the first pair of arm  90  are provided with outwardly extending protrusions or buttons  100 . Each button or protrusion  100  of the first pair of arms  90  has a top surface  102 , a pair of side surfaces  104  which are flat and parallel, an outer surface  106  and a bottom surface  108 . 
     The upper half of the cylinder  16  is provided with a first pair of elongated openings  112  which extend completely through the cylindrical wall  16 . The openings  112  are elongated and of generally rectangular cross section. Such openings  112  are located approximately 180° apart for receiving the outwardly extending protrusions or buttons  100  of the first pair of arms  90  thereby preventing movement of the washer  40  towards the lower end of the cylinder  16  when viewed in FIG. 10 thus preventing the washer  40 , syringe  12  and needle  14  from exiting the cylinder  16  when the spring means or compression spring  38  is activated and thereby applies an upward thrust to the washer  40 . The top surfaces  102  of the protrusions or buttons  100  are angled upwardly to facilitate the movement of the protrusions  100  into the corresponding elongated openings  112  in the cylinder wall  16  to thereby assist in catching and holding the washer  40  in position in the elongated openings  112 . The bottom surfaces  108  of the protrusions  100  of the first pair of arms  90  are inclined upwardly as viewed in FIG. 16 to permit the washer  40  to move towards the bottom wall  50  of the cylinder  16  without catching in the elongated openings  112 . Each arm  90  and  92  has inner and outer cylindrical surfaces  114  and  116 . 
     It should be understood that the elongated openings  112  provided in cylinder  16  are offset from the center, with the protrusions  100  of the first pair of arms  90  being offset from the centerline of each arm  90  as best illustrated in FIG.  16 . 
     The arms  92  of the second pair of arms are symmetrical about the centerline of each arm. The upper end of each arm has a centrally located protrusion or button  120  and inner cylindrical surface  122  and an outer cylindrical surface  124 . The top surface, side surfaces, outer surface, and bottom surface of each protrusion  120  are flat. With such a construction, the top and bottom surfaces are parallel, the side surfaces are parallel and the outer surface is cylindrical. 
     The cylinder  16  further includes a second pair of openings in the form of inverted T-shaped slots  126 . The slots  126  are located in the upper portion of the cylinder  16  and are located 180° apart. The inverted T-shaped slots  126  are constructed and arranged to receive the protrusions or buttons  120  provided on the second pair of arms  92  when the washer  40  is in the upper portion of the cylinder  16  as viewed in FIG.  11 . At such time the protrusions  120  fill the T-shaped slot  126 . The purpose of the protrusions  120  is to stop downward movement and the unlocking of the washer  40  when required. In addition, means are provided for urging the protrusions  120  inwardly to disengage same from the slots  126  so that downward movement of the washer  40  can occur. 
     The cylinder  16  adjacent the upper end of the cylinder immediately below the oval entrance  44  is provided with a pair of elongated flexible release arms  130 . The arms  130  overlie the T-slots  126 . The free end  132  of each arm  126  is provided with a rounded bulge or formation opposite the protrusions  120  when in the locked position as viewed in FIG.  11 . When it is required to release the washer  40 , pressure is applied to the flexible release arms  130  so as to move the formations  132  inwardly against the protrusions  120  of the second pair of arms  92  to thereby disengage the protrusions  120  from the T-shaped slots  126 . Thereafter, pressure may be manually applied to the syringe  12  by moving the plunger  26  downwardly from the position illustrated in FIGS. 10 and 11 to the positions illustrated in FIGS. 8 and 9 . This results in the washer  40 , syringe  12  and needle  14  moving downwardly into the bottom of the cylinder  16  where the syringe  12  is locked in the down position by the thumb latch  42  as illustrated in FIG.  8 . At such time, the compression spring  38  is compressed as viewed in FIGS. 8 and 9 between the bottom portion of the washer assembly and the spring seat  56 . 
     The release arms  130  and cylinder  16  are molded an integral unit from plastic material taken from the group of plastics including polypropylene and Nylon. As mentioned previously, the cylinder  16  is made from a clear plastic material which permits viewing of the syringe  12  including the graduations  36  and the amount of medications remaining in the syringe. 
     With the washer construction just described, it should be noted that all four arms  90  and  92  assist or aid in the stopping of the upward movement of the syringe  12  while still maintaining the orientation of the washer  40 . This is accomplished by the outer tips or ends of the protrusions or buttons  100 ,  120  being seated in the channels  85  and moving upwardly or downwardly in the channels  85 . The arms  90  of the first pair of arms and the corresponding protrusions or buttons  100  which cooperate with the elongated openings  112  provided in the cylinder  116  are designed primarily to stop upward movement. As mentioned previously, the buttons  100  are angled upwardly to allow a better attachment, catch and to hold the washer  40  in the openings  112 . This keeps the washer  40 , syringe  12  and needle  14  from exiting the main housing unit or cylinder  16  when the spring  38  is activated and upward thrust is applied to the washer  40 . As also mentioned previously, the underside or bottom surface  108  of protrusions or buttons  100  are also angled upwardly to allow easy downward movement of the washer  40  without hanging in the elongated holes  112 . Such holes  112  are offset from the center position of the inner channels  85 . This has been done to eliminate an extra step in the manufacturing of the dies for this product. The protrusions or buttons  100  on the ends of the arms  90  are the only elements that are offset on the washer  40 . It will be appreciated that the channels  85  for the arms  90  have also been modified to match the position of the buttons  100  within the main housing unit or cylinder  16 . 
     In further summary of the invention, the second set of arms  92  and the corresponding protrusions or buttons  120  are utilized for stopping downward movement and also unlocking the washer  40  so downward movement can thereafter occur. When the protrusions  120  are set into the T-shaped slots  126 , which are located on both sides of the main housing unit  16 , the protrusions  120  keep the washer  40  from being pushed down into the bottom of the main housing unit or cylinder  16 . However, when the pressure is applied inwardly by the thumb and index finger on the release arms  126 , the buttons  120  are flexibly forced inwardly, disengaging themselves from their seated position within the slots  126 . This allows or permits manual pressure to be applied by the operator to move the washer  40 , syringe  12  and needle  14  downward into the bottom of the main housing unit  16 , where the combination of the washer, syringe and needle are locked in the down position by the novel thumb latch  42 . At this point, injections can be performed. It should be noted that the needle  14  does not need to be attached to the washer for this process to take place. It will generally be attached to the washer  40  after the abovementioned steps have been completed. 
     It will be observed that the flexible release arms  130  overlie the T-shaped slots  126  so that when they are pushed inwardly against the protrusions  120 , release of the washer  40  from its seated position is achieved. The release arms  130  are the means by which the entire device is unlocked and prepared for injection use. The release arms  130  have a slightly rounded bulge or formation  132  on their inner ends created for comfort and for added torque when pressure is applied by the fingers of the operator. The release arms  130  are molded into the main housing unit or cylinder  16  and are able to flex inwardly and outwardly to a point needed to cause release or locking depending on the desired setting. 
     The washer  40  is equipped with the Luer Lock, Luer-Slip male and female attachments that are standardized by the International Standards Organization and the American Standards National Institute to fit all Luer Lock and Luer-Slip tipped syringes. The use of such standards assist in providing a fully automated retractable safety syringe. 
     The oval end  44  of the cylinder  16  is provided with a pair of reinforcing ribs  140  (FIG. 3) which are located on opposite sides of the enlarged opening on the interior surface thereof. The reinforcing ribs  140  as illustrated in FIG. 8 also serve as stops to prevent the syringe  12  from moving downwardly. Such ribs  140  also assist in preventing the syringe  12  from crushing the compression spring  38 . 
     It will now be apparent that the medical technicians or operators can use a needle protection holder  10  with one hand allowing the technicians the freedom to perform other tasks with their other hands. The holder  10  is designed to protect medical technicians and personnel from exposures to infectious diseases. The holder  10  is designed to accept more than one type of syringe and to meet national standards. In operation or use, once the needle is placed in the body of a patient or animal using the needle protection holder  10 , the needle  14  will never contact the open air, another patient or the technician unless the technician takes a direct action to unlock the assembly in the manner described previously. It would be appreciated that the holder  10  could be reused. Earlier devices which have claimed to isolate the needle after use have certain drawbacks or restrictions. Some devices require you to use all the contents of the syringe before it retracts the needle into the provided enclosure. Still others are made to be used only with the manufacturer&#39;s syringes which limits the ability of hospitals or clinics to choose to purchase the type of syringe which best suits their purpose and budget. 
     Thus, with the present invention the holder  10  provides choices for the medical technicians and for the hospitals. Medical personnel can choose what syringe to use with the present invention, where and when to retract the needle and whether or not the needle protection holder is to be used again. The holder permits it to be used in the same manner as a Luer Lock syringe would normally be used, with the additional ability to protect all medical personnel from deadly needle sticks or punctures. 
     It will be further understood that the embodiment of the invention described herein is to be taken as a preferred example of the same and that various changes in size, shape and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the claims which follow. Further, while the principles of the invention have now been made clear, there will be immediately obvious to those skilled in the art certain modifications of structure, arrangement, proportions, elements, materials and other components used in the practice of the invention which are particularly adapted for specific environments and operating requirements without departing from those principles.

Technology Category: 4