Abstract:
A device for distributing substances includes distribution container ( 1 ) receiving a substance. The container has a closing unit ( 3 ) provided with a canula ( 11 ) for the substance to be distributed. The outer end ( 15 ) of the canula protrudes from the closing unit ( 3 ). A safety device ( 5, 17 ) can alternate between a protective state in which it covers the outer end ( 15 ) of the canula ( 11 ), and a user state for the distribution of the substance from the canula ( 11 ).

Description:
FIELD OF THE INVENTION 
   The present invention relates to a device for distributing substances. A primary, but not exclusive, application of the device involves delivering a desired volume of a medium, especially a liquid medium, into a receptacle. Preferably, the medium to be delivered is an additive which is introduced, for example, as an admixture of an active ingredient into a fluid located in the receptacle. The receptacle can be an infusion container with contents with which the medium is to be admixed as an additional active ingredient. 
   BACKGROUND OF THE INVENTION 
   For this purpose, the delivery device is conventionally a syringe with a hypodermic needle which punctures the perforable closure or plug of the receptacle, for example, an infusion container. After puncture, by pressing the syringe, the medium is injected into the receptacle. In this process the preparatory working step of filling the syringe is necessary, in which the desired amount of the medium from a storage container is transferred into the syringe or the syringe is filled from a conventional vial which contains the measured dose of the pertinent medium. These working steps of transfer are on the one hand time-consuming, because the hypodermic needle and syringe must be unwrapped, the hypodermic needle mounted on the syringe, the vial opened or punctured and the syringe must be drawn up. On the other hand, in these measures, a major risk exists of contamination of the medium. Another problem in these delivery devices is the danger of injury to which the user is exposed during handling and which may be caused by the tip of the hypodermic needle. In this respect, a known delivery device, disclosed in U.S. Pat. No. 4,735,618, includes a safety device which has a safety body covering the end of the hypodermic needle and which can be moved from the effective protective state into the inactive state intended for delivery of the medium from the hypodermic needle. For this purpose, the safety body can be pushed along the hypodermic needle between an advanced protective position on the end of the hypodermic needle and the retracted state of use. 
   The disadvantage in this known device is that there are no provisions against unintentional movement into the position of use, in which the end of the hypodermic needle projects exposed. The known device can only be safeguarded after completed use by fitting the tip of the hypodermic needle in a receiving recess of the safety body after it has been advanced beyond the tip of the hypodermic needle after use of the device. The known device is therefore unsatisfactory from the standpoint of safety. 
   SUMMARY OF THE INVENTION 
   Objects of the present invention are to provide a device which offers increased safety against injuries during transport, storage and use. 
   These objects are basically achieved in the present invention by a delivery device which has a protective cover which can be removed from the delivery container and which encloses the end of the hypodermic needle. Not only is the danger of unintentionally pushing back the safety body of the safety device avoided, but in addition increased protection against contamination is achieved. 
   If the outer end of the hypodermic needle is designed to penetrate the perforable closure of the container which holds the medium which is to be delivered, when the closure is punctured the safety body can be pushed back by contact with it out of its advanced protective position on the end of the hypodermic needle into the position of use. After the hypodermic needle is pulled out of the closure, the safety body can be pushed forward again into the protective position. In this embodiment handling is especially simplified. 
   Preferably, the protective cover has a finger-grip knob as purchase for twisting the protective cover off of the delivery container. 
   As the safety body, the safety device can have an annular body movably guided on the section of the hypodermic needle projecting out of the closing unit. The annular body is connected to the closing unit by an elastic holding means which produces a holding force, is held by force-fit by the holding force of the holding means in the advanced protective position covering the end of the hypodermic needle, and can be pushed back against the holding force along the hypodermic needle into the position of use. The indicated annular body on its free face forms an annular broadened contact surface projecting on the forward point of the safety device radially over its other parts. By way of the widened contact surface, reliable contact behavior of the annular body with the puncturable point of the container on its removal opening results. Furthermore, as a result of the contact surface, when the perforable closure of the delivery container is punctured, the hypodermic needle cannot jam or be damaged on the sensitive tip. 
   The holding means can be formed by support elements which are divided by means of joints and which are articulated to the annular body and the closing unit, respectively. In the protective position, the support elements extend essentially parallel to the hypodermic needle. When the annular body is pushed back into the position of use along the hypodermic needle, the support elements extend in the position which is spread out from the hypodermic needle. 
   Preferably, the support elements are rod-like plastic parts, are molded in one piece to the closing unit, and are divided by bending joints at approximately half the length. In this execution, the inherent elasticity of the material of the support elements makes it possible for the annular body to be advanced automatically again at least partially against the front end of the hypodermic needle after being pushed back into the position of use, for the annular body therefore to return automatically back into the protective position, or after using the device for it to be advanced simply slightly farther forward. Since the bending joints can completely fold down laterally, the rod-like plastic parts which form the respective bending joint are placed in contact on top of one another so that a high penetration depth of the hypodermic needle into the delivery container can be achieved. Also perforable closures with the corresponding thicknesses of the delivery container can thus be punctured in a controlled manner by the hypodermic needle. 
   In one especially advantageous embodiment, the closing unit bears a snap ring which encloses the support elements and which can be removed from the closing unit and can be pushed along the support elements toward their bending joints to lock them in the position corresponding to the protective position. Catch notches can be provided on the bending joints into which the snap ring can snap so that the safety device is detachably locked in the protective position in which the annular body protectively encloses the outer end of the hypodermic needle. 
   The delivery container can be a plastic container produced using the known Bottelpack® process. The closing unit as an insert part is inserted into its open end before closing by means of the protective cover. 
   The body of the insert part in the central area contains the hypodermic needle which is located continuously in it. Its inner end projects slightly out of the body of the closing unit against the interior of the delivery container. The insert part, which forms the closing unit, has a membrane as a blocking element between the facing inner end of the hypodermic needle and the medium which is located in the delivery container. If the pressure of the medium which is located in the delivery container is increased, the blocking element is pressed against the end of the hypodermic needle and is punctured by it. 
   The increase of the pressure of the medium and the resulting puncturing of the membrane can be implemented by compressing the delivery container. 
   Other objects, advantages and salient features of the present invention will become apparent from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring to the drawings which form a part of this disclosure: 
       FIG. 1  is a side elevation view of a delivery device according to an embodiment of the present invention in an operating state before use, i.e., with the protective cover mounted; 
       FIG. 2  is a side elevational view in section of the device of  FIG. 1 ; 
       FIG. 3  is a side elevational view in section of the device of  FIG. 1 , but with the protective cover removed; 
       FIG. 4  is a side elevational view in section of the device of  FIG. 1  in an operating state where the device has been pushed into the perforable closure stopper of an infusion container; 
       FIG. 5  is a side elevational view in section of the device of  FIG. 1  in an operating state where the delivery container of the device is being squeezed out; 
       FIG. 6  is a side elevational view in section of the device of  FIG. 1  in an operating state where the delivery container has been squeezed out and withdrawn from the closure stopper, and 
       FIG. 7  is a side elevational view in section of the device of  FIG. 1  in an operating state where the delivery container has been squeezed out and which corresponds to the protective position of the safety device. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In the drawings, the delivery container is designated as a whole as  1 . It is an ampule-like plastic container which has been produced using the known Bottelpack® process. The delivery container has a wall  2  provided with folds and made bellows-like, so that the delivery container  1  can be squeezed out from the configuration shown in  FIGS. 1 to 4  to that shown in  FIGS. 5 to 7 . In the neck area, a closing unit  3  is inserted into the delivery container  1  as an insert part. Several components are molded onto the body of the closing unit which is molded from plastic. Among others, a safety device  17  is provided, which, before using the delivery device, is protected by a protective cover  5  molded on at a predetermined breakage point  7 , see  FIGS. 1 and 3 , to the body of the delivery container  1 . The cover has a laterally projecting finger-grip knob  9  which is used as purchase to twist the protective cover  5  off the delivery container  1  at the predetermined breakage point  7 .  FIG. 3  shows the same operating state of the device as  FIGS. 1 and 2 , but with the protective cover  5  removed. 
   As is especially apparent from  FIGS. 2 and 3 , the body of the closing unit  3  in the central area is penetrated by the hypodermic  11  needle. The needle inner end  12  projects slightly to the inside of the delivery container from the body of the closing unit  3 . Between the inner end  12  of the hypodermic needle  11  and the interior of the delivery container  1 , there is a membrane  13  which is part of the insert part of the closing unit  3 . 
   The hypodermic needle extends from the outer end of the body of the closing unit  3  to a length which corresponds approximately to the length of the syringe hypodermic needle.  FIGS. 2 ,  3 , and  7  show operating states in which the projecting outer end  15  of the hypodermic  11  needle is covered, i.e., protected, by safety device  17  which is in its protective position. 
   The safety device  17  is molded in one piece to the body of the closing unit  3  and has an annular body  19  which can be moved on the hypodermic needle  11  and is located in the protective position (see  FIGS. 2 ,  3 , and  7 ) on the outer end  15  of the hypodermic needle  11  to cover this end of the hypodermic needle, i.e., the tip of the needle. The annular body  19  is connected in one piece to the body of the closing unit  3  by support elements  21  of a rod-like shape which are molded on in one piece. The connecting points of the support elements to the annular body  19  and the body of the closing unit  3  are flexible in the manner of bending joints. In addition, at approximately half of the length of the support elements  21 , bending joints divide the support elements  21 . If the annular body  19  is pushed out of the protective position into the position of use of the device along the hypodermic needle  11 , see  FIGS. 5 and 6 , the sections of the support elements  21  bordering the bending joints  23  swivel so that they are spread out from the hypodermic needle  11  and are folded as is shown in  FIG. 5 . 
     FIG. 5  and  FIG. 4  show the device in the state in which the hypodermic needle  11  with its front end  15  has punctured the perforable closure  25  of an infusion container  26 . Here, the annular body  19  is pushed back into the position of use along the hypodermic needle  11  out of the protective position aligned with the outer end  15  of the hypodermic needle. By compressing the bellows-like wall  2  of the delivery container  1  (see  FIG. 5 ), the pressure of the medium it contains is increased so that the membrane  13  is pressed against the facing inner end  12  of the hypodermic needle  11  and is punctured by it. Compressing the delivery container  1  further leads to the medium contained in it being squeezed out into the infusion container  26  so that a dose of an additive or active ingredient which corresponds to the contents of the delivery container  1  is added to the contents of the infusion container  26 . 
     FIG. 6  shows the operating state after the delivery container  1  has been squeezed out and is withdrawn again from the closure  25  of the infusion container  26 . As a result of the inherent elasticity of the support elements  21 , the annular body  19 , which had been pushed back beforehand out of the protective position when the hypodermic needle is inserted into the closure  25  by contact therewith against the elasticity or holding force of the support elements  21 , is automatically advanced again by the force of elasticity in part against the end  15  of the hypodermic needle. 
     FIG. 7  shows the operating state of the device after its completed use. The projecting outer end  15  of the hypodermic needle  11  is secured again by the safety device  17 , although the protective cover  5  is no longer mounted. For this purpose, a snap ring  29  sits removably on the body of the closing unit  3 , is removed from the closing unit, and is advanced along the hypodermic needle  11 . Sliding the snap ring over the support elements  21  brings them out of the position shown in  FIG. 6  to the hypodermic needle  11 , with the annular body  19  being advanced as far as the end  15  of the hypodermic needle  11 . On the bending joints  23  the support elements  21  have molded catch notches  30  into which the snap ring  29  fits (see  FIG. 7 ). 
   After the snap ring  29  catches in the catch notches  30  on the bending joints  23  of the support elements  21 , the hypodermic needle  11  is covered by the annular body  19  which covers its end, in spite of the removed protective cover  5 . The now emptied device can then be safely disposed of. The delivery device of the present invention can be advantageously used, not only for adding the desired volumes of liquid media to infusion containers, but can also be used equally for the delivery of liquid or gaseous and/or particle-laden media, to the extent their delivery by way of hypodermic needles is possible or necessary. 
   While an embodiment has been chosen to illustrate the invention, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.