Safety shield system for prefilled syringes

Background of the Invention

1. field the invention

The Field of the invention relates to shield systems to protect containing against injuries caused by needles and in such systems Syringes.

2. Brief Description of the prior art

splash are well known medical devices for administering drugs to patients. They are also well known to other purposes the field of medicine. Generally as prefilled syringes those referred to, which at a selected dosage of a drug or other substance by a pharmaceutical manufacturer for distribution filled to the final consumer will. They often consist of a glass or plastic drum, which contains the medicament or other substance, and a piston which is slidably mounted in the drum. On End of the barrel includes a needle or the like, it is attached, or a connector for a needle assembly, as for example, a Luer connection. The term "needle" as used herein is, should therefore be generally understood that it different Types of piercing elements or compounds includes either pointed or blunt. The other end of the syringe is open around the insertion a plunger to allow. The ram Allowed the user to exert on the piston a manual force which causes that the medicament through the needle or other piercing member is administered.

The Using a sharp penetrating member carries a risk of accidental needle injury. To avoid such accidents, have stiff known hypodermic syringes from the prior art cylindrical safety shields telescoped over the Syringe barrel are pushed. These shields can between retracted positions where the needles for use free are, are brought in extended positions where the needles are surrounded by the shields. The US Patent Nos. 4,425,120, 4,573,976, 4,850,994 and 4,923,447 disclose various shield systems for hypodermic syringes. The latter two patents disclose shields which by actuated spring will. Normally, it is desirable lock the needle shields in the protected position, and a number of known constructions see such a lock in front. Some systems, such as those described in U.S. Patents No. 5,201,708, 5,242,240 and 5,318,538 are disclosed, are designed, that allows the shields is retracted from their locked, extended position to become.

On Shielding system to protect the penetrating a prefilled syringe is described in European Patent publication No. <patcit><text>EP 0740942 A1</text></patcit> disclosed. The disclosed system includes a holder connected to the flange of the syringe barrel is, as well as a shield telescopically seated on the holder. Two hands needed to actuate the system.

The WO97 / 14455 discloses a shield protection system having the features of the preamble of Claim first

Summary the invention

The Invention relates to a safety shield system for a syringe and such a system in combination with an arrangement is, which functions as a syringe. According to preferred embodiments of the system, the user is able to shield a to cause needle in that it after the injection of the contents of of the syringe barrel on the plunger of Syringe exerts a pressure. The shield may accordingly under Using one hand only be automatically extended. There there is no need for any purpose in hand the close to bring the needle, the risk of injury is reduced by a needle.

According to the objectives of the invention is a medical device is provided which operable automatically Shielding system that is sitting on a syringe barrel includes. The system includes a holder defining a cavity. The syringe barrel extending at least partially and preferably almost entirely within the Cavity. The drum can be displaced in the holder. A support member is arranged on the holder and engageable with the drum in engagement. This element prevents the drum decoupled from holders becomes. A shield is mounted on the holder and at least a portion of the drum arranged. The shield is axially relative to the Holder between a retracted position and an extended position movable. They will cover the needle tip when extended in the is position. A spring is engaged with the shield and in presses it in the extended position. A first stop member disposed on the shield, and a second stop element is disposed on the bracket. The second stop member with the first stop element is engageable when the shield in is the retracted position. The force of the spring is in itself not sufficient to provide a loosening to cause the first from the second abutment member. The drum is operatively connected to the shield, so that a sufficient axial movement of the barrel causes axial movement of the shield, leading to a loosening the first and second stop element is sufficient. Such movement of the drum is usually caused by a pressure, which after a full injection the contents of the drum is exerted by the user of the syringe on the plunger. After dissolving the first and second stop member causes the spring, that the shield moves to the extended position.

The proximal end of the holder is preferably designed so that it connects the flange and supports the proximal end of the syringe barrel may be present. The axial movement of the shield is preferably by a set Verriegelungsarretierungen that on the holder are formed is limited. This movement could alternatively be limited by a tether, which holder the and the shield connects. The shield is preferably positioned in the holder so that the spring with the first stop member is engaged. The opposite end of the spring can against any suitable surface to press, such as the flange on the syringe barrel, if present, or a collar part of an end cap slidably in the holder is positioned.

The Shielding system of the invention consists of a holder, a shield, a spring and preferably an end cap. The holder is for receiving at least one designed flanged portion of the barrel of a syringe and has axially spaced, opposite each other lying abutment surfaces comes to rest on the flange. corresponds to the distance between these surfaces the distance over which the syringe can move axially with respect to the holder, after it is mounted on the latter. The shield is slidably mounted on the holder is mounted and is movable between a retracted position and an extended position to move. A spring presses the shield in the extended position. The holder includes a stop member is engageable with the shield into engagement to it in the retracted to maintain position. caused Sufficient axial movement of the shield loosening of the stop member, thereby allowing the spring, the shield is in to bring the extended position. An end cover is preferably integrated in the system to the position of the spring prior to insertion to get a syringe in the holder upright.

The allows screening system the safe use of prefilled Spraying, even if it for other sharp medical devices, filled such as immediately prior to use syringes can also be used. When used with a syringe allows the system determines that the contents of the syringe in a conventional manner forced out can be. A continuing and increasing pressure by the User is exerted by the injection on the plunger, causing that the syringe barrel to move axially, whereby the shield axially is moved. Such displacement causes release of the Stop element, and that the spring, the shield on the Needle of the syringe moves. In this way a protection against Needle injuries provided.

Summary tHE dRAWINGS

<figref idrefs="S20">1</figref> is an exploded perspective view a medical Shows apparatus according to a first embodiment of the invention;

<figref idrefs="S21">2</figref> is a perspective view of the assembled medical Devices from above;

<figref idrefs="S22">3</figref> is a sectional side view of the same;

<figref idrefs="S23">4</figref> is a section through the same after the actuation of the shield system the apparatus;

<figref idrefs="S24">5</figref> is an enlarged section of the proximal portion of the device prior to actuation of the shield system;

<figref idrefs="S25">6</figref> is an enlarged sectional view, showing a portion of the apparatus of the distal portion Syringe holder of the device following actuation of the shield system includes;

<figref idrefs="S26">7</figref> is a sectional side view of the apparatus with respect to the view of <figref idrefs="S22">3</figref> is rotated by 90 °;

<figref idrefs="S27">8</figref> is a sectional side view of the apparatus after actuation of the Shielding system, the opposite the depiction of <figref idrefs="S23">4</figref> is rotated by 90 °;

<figref idrefs="S28">9</figref> is an enlarged sectional view of the the proximal end portion of the apparatus after actuation of the Shield system;

<figref idrefs="S29">10</figref> is an enlarged sectional view similar to in <figref idrefs="S25">6</figref> shown, but with respect to this rotated 90 °;

<figref idrefs="S30">11</figref> is is an enlarged partial perspective sectional view the distal end of the device after actuation of the Shield system;

<figref idrefs="S31">12a</figref> is a front view of the syringe holder the apparatus;

<figref idrefs="S31">12b</figref> is a front view of an alternative embodiment of the syringe holder;

<figref idrefs="S32">13</figref> is a perspective view of the shield system, which in of the <figref idrefs="S20">1</figref> - <figref>12</figref> shown medical device is used;

<figref idrefs="S33">14</figref> is an exploded perspective view a medical Device according to a second embodiment of the invention;

<figref idrefs="S34">15</figref> is a perspective view of the same;

<figref idrefs="S35">16</figref> is a sectional view of the same, showing the device prior to activity the shield system;

<figref idrefs="S36">17</figref> is a cross-sectional diagram of the device after actuation Shield system;

<figref idrefs="S37">18</figref> is an enlarged sectional view the proximal part of the same immediately after an operation of the Shielding system, and

<figref idrefs="S38">19</figref> is an enlarged sectional view, the part of the device following actuation of the shield system shows.

Detailed Description of the Invention

A medical device <figref>10</figref> for injecting a drug in a patient is in the <figref idrefs="S20">1</figref> - <figref idrefs="S30">11</figref> shown. The device comprises a prefillable syringe <figref>12</figref> and an affiliate of the syringe shield system <figref>14</figref>,

splash are usually of a generally cylindrical portion as a drum is referred to, a needle or other piercing element or a connecting element secured to one end of the drum , and a piston or stopper slidably in the drum is positioned. The needle can removably mounted on the drum be, but it is likely that they permanently on the Drum is attached, when the drum is made of glass.

glass tumblers are usually filled in in advance Syringes used and usually contain a single dose of medication. Pre-filled Syringes, which are made of plastic, are also on known in the art. The shield system<figref>14</figref>, this one disclosed, is used with a prefilled syringe a drum <figref>16</figref>, A cannula such as a needle <figref>18</figref>. which is permanently secured on the drum, the drum in a slidably positioned pistons <figref>20</figref> and a plunger <figref>22</figref> having, which is engageable with the piston in engagement. The syringe barrel<figref>16</figref> contains a radially outwardly extending flange <figref>24</figref>Which for coupling the syringe with is used the shield system.

The Shielding system of the invention <figref>14</figref> contains a holder <figref>26</figref>, Coupled to said holder shield <figref>28</figref> and a feather <figref>30</figref>, also contains it preferably has a support end cover <figref>32</figref>Associated with a End of the spring is engaged. Except for the spring, all the components of the system from a semi-rigid plastic material such as Polypropylene. The spring is preferably a metal coil spring.

Of the holder <figref>26</figref> preferably consists of an elongated generally cylindrical body <figref>34</figref>, of the a generally cylindrical cavity <figref>36</figref> defined. Of the Holder has a first and a second open end, the access to the cavity offer. A flange<figref>38</figref> extending radially outward the holder body close the second open end. The flange and the body of Holder are for ease of handling during the execution of a Injection constructed. For injection only one hand should be required.

The inner surface the holder has a truncated portion <figref>40</figref> on, which is the second open end adjacent. A first stop surface<figref>42</figref> is formed at the inner end of this surface. A second stop surface <figref>44</figref> is through the holder body formed in the opposite direction to the first abutment surface. As described below corresponds to the axial distance between these surfaces the axial distance, might be taken out the syringe with respect to the holder move, is this not the same. The inner diameter of the holder, on the stop surfaces measured is smaller than the distance between the edges of the syringe flange <figref>24</figref>, After the syringe has been inserted far enough into the holder, so that the flange <figref>24</figref> between the stop surfaces <figref>42</figref>. <figref>44</figref> to lie comes, it is therefore slidably coupled to the holder. The feather <figref>30</figref> presses the syringe against the first stop face <figref>42</figref>,

A or more openings, In suchplay the openings <figref>46A</figref>. <figref>46B</figref> are formed in the holder body. These openings to each other in opposed relation and relative to the Axis which the maximum dimension of Halterflanschs <figref>38</figref> having, offset by 90 °. The openings extending between the first abutment surface <figref>42</figref> and a point almost on the half to the first open end of the holder. The sizes of the openings are in dependence selected by the degree of flexibility that for the holder body desirable is. The flexibility of the holder body or shield may also be provided by the materials, comprising these elements, as well as by their wall thicknesses. Each contains part a relatively wide portion between the first abutment surface <figref>42</figref> and the flange <figref>38</figref>,

On generally annular stop element <figref>48</figref> is on the holder in the form of a is provided inwardly extending protrusion. alternative refer to a number (not shown) of discrete projections used will. The stopper member through the openings<figref>46A</figref>. <figref>46B</figref> interrupted and contains an inclined surface, facing the second open end of the holder body.

On Pair of first detents <figref>50</figref> is at said first open End of the holder or provided in its vicinity. Each first detent is in the form of a protrusion extending radially from the body of the holder by extends inwardly. As in<figref idrefs="S31">12a</figref> shown are the first detents <figref>50</figref> in an opposite relationship to each other. Alternatively, a single, continuous detent in the form of an annular collar <figref>50 '</figref> be provided, as in <figref idrefs="S31">12b</figref> shown.

On second pair of detents <figref>52</figref> is provided on the holder and of the first axially spaced detents. Each of these detents <figref>52</figref> is on an extending axially poor <figref>54</figref> formed with the holder body <figref>34</figref> integrally and respect this is pivotable. The end surface the respective detent to the first open end of the holder shows, is substantially perpendicular to the longitudinal axis of the holder. A inclined end surface is provided on the opposite side of the respective locking and shows to the second open end.

The shielding <figref>28</figref> consists of a substantially cylindrical body <figref>56</figref>, This is preferably so small that it in its diameter Holder can be positioned and so large that it over the drum <figref>16</figref> the Syringe fits. A stop member<figref>58</figref> in the form of a radially outwardly extending collar is on the body <figref>56</figref> the shield formed. This stop member has an inclined surface with the inclined surface the stop member <figref>48</figref> brought on the holder engaged is. Axially extending ribs<figref>62</figref> can to Contacting a syringe barrel on the inner surface of body be provided. openings<figref>60</figref> in the shield give the shield body flexibility. The flexible Engaging the syringe barrel by the ribs allows the shield, in terms of to move the drum without between the drum and the shield side play exists.

The feather <figref>30</figref> is designed to fit over the vote, that one end of the same against the shield stop member <figref>58</figref> suppressed. The opposite end of the spring presses against the end cover <figref>32</figref>,

The Spring can be used, that the shield causes is axially upon axial movement of the syringe barrel move when they fully is compressed, when the shield is in the retracted position. Direct contact between the syringe <figref>24</figref> and shield, as in the preferred embodiment is provided, would be at such an arrangement unnecessary. Of the Operation of the device can be carried out regardless of whether the shield, the spring, the end cap and the syringe barrel are in direct or indirect contact, so long as axial movement of the Syringe barrel causes axial movement of the shield. As discussed below, is the use of an end cap optional.

The end cover <figref>32</figref> contains a cylindrical body <figref>64</figref>. of the body <figref>34</figref> of can be used holder. One end of the spring<figref>30</figref> is insertable into the end cap. An annular wall <figref>66</figref> is at one end of the cylindrical body <figref>64</figref> scheduled and is preferably connected thereto. This wall extends radially outwardly and radially inwardly with respect to of the cylindrical body <figref>64</figref>, The radially outwardly extending part of the wall is to contact the first abutment surface <figref>42</figref> designed, so they behind the frustoconical portion at the second open end can engage the holder. He is used, the spring<figref>30</figref> in the to keep holder in place, thereby allowing the shield system is allowed to be manufactured as a subassembly which the Syringe does not contain. The radially inwardly extending portion of the wall is designed so that he between the first end of the spring <figref>30</figref> and the syringe <figref>24</figref> in may engage. Accordingly, it is protect this flange from direct contact with the spring. This Is desirable to protect where the shield system in conjunction with a glass syringe is used to breakages to be avoided. In the absence of the optional end cover<figref>32</figref> takes over the first stop surface <figref>42</figref> the Function of the holder of Syringe in the holder by directly the syringe is engaged. The special design of the support member or of the holding elements is immaterial, as long as the syringe during slidably coupled to the use of the device with the holder remains. Axial movement of the syringe causes corresponding axial movement of the end cap until the inwardly extending Part of the annular wall <figref>66</figref> with the first end of the shield <figref>28</figref> in Engages. Without the end cap of the syringe would<figref>24</figref> directly with this surface engage.

it A description of the installation and use of this preferred embodiment of Invention. The shield<figref>28</figref> is slidably mounted on the holder mounted by being inserted through the second open end. The engagement of the stop members <figref>48</figref>. <figref>58</figref> limited this insertion. The Spring is inserted through the second open end of the holder as well as the Shield until the shield stopper member <figref>58</figref> incident. As a final step before delivery of the screening system to the end user is the end cap <figref>32</figref> on the exposed mounted end of the spring and through the second open end of the holder pressed. The spring is during this step is compressed substantially. The shield is resiliently pressed to the first open end of the holder while the end cap to pressed second open end becomes. No part of it may be due to the engagement of the stop elements<figref>48</figref>. <figref>58</figref> respectively the annular wall <figref>66</figref> With the first stop surface <figref>42</figref> move. The Force of the spring <figref>30</figref> is not sufficient to ensure that these elements to solve. The shield system in the in <figref idrefs="S32">13</figref> shown Form are delivered to end users or pharmaceutical manufacturers.

The shielding system <figref>14</figref> takes through the second open end the holder a syringe on an appropriate size. The system shown here is constructed with a flange for receiving a syringe. The Syringe is inserted into the shield until the flange <figref>24</figref> Behind the first stop surface <figref>42</figref> locks. The end cover <figref>32</figref> is easily during this process shifted. Since the needle of the syringe at this time is usually protected by a cover , it may be safely coupled to the shield system.

The to dissolve the stop elements <figref>48</figref>. <figref>58</figref> required power should be greater than be the force for pushing the contents of the syringe barrel is required. The ram is for moving the piston <figref>20</figref> down the syringe barrel used until the contents of the drum was fully pressed out. (The cover is of course removed before injection.) The content the drum of a prefilled Syringe usually corresponds a single dose of the prescribed drug.

After the removal of said needle <figref>18</figref> from the patient turns the User a greater force on the plunger as while injection. This force causes an axial displacement of End cap, the spring and the shield with respect to the holder. The distance between the annular wall <figref>66</figref> the End cover (or the flange <figref>24</figref>) And the second abutment surface <figref>44</figref> enough made to allow the second stop element <figref>58</figref> allow to be axially to move far enough to the retention by the first stop member <figref>48</figref> by overcome the force of spring becomes. In the preferred embodiment This is accomplished when the inclined surfaces of the stop elements to one another slide past. The first stop member<figref>48</figref> is also while sliding radially offset what on the flexibility of the holder body part is located, which is adjacent to it.

After this the stop elements <figref>48</figref>. <figref>58</figref> were dissolved from each other, the spring extends <figref>30</figref> quickly, thereby causing is that the shield with respect to of the holder and the syringe barrel is axially displaced. The stop member<figref>58</figref> emotional at the second detents <figref>52</figref> over what they to that brings them to the outside be distracted and finally inwards again to its original return position. Finally comes it with the first detents <figref>50</figref> engage After a such engagement is the needle <figref>18</figref> their entirety and permanently covered by the shield, as shown in <figref idrefs="S23">4</figref> and <figref idrefs="S27">8</figref> shown is. The shield may due to the engagement of the stop member<figref>58</figref> With the second detents not be retracted so far that the Needle tip is exposed. They can not be removed from the holder, since the stop member <figref>58</figref> not to the first detents <figref>50</figref> past can move.

Of the Process described above is particularly secure since it using only a single run can be. There is no second hand required to press a button or any other actuator to trigger to use the pen. The risk of inadvertent actuation of the Shielding by inadvertent contact with an actuating button excluded. also is for most people using a one-handed system easier. it is easy to see that the shield system for use adjusted with syringes of various shapes and sizes without major modifications can be.

The Extending a shield in response to the axial displacement a syringe barrel with respect a holder provides a secure and effective protection against needle injuries . The preferred embodiment of the invention as described above, provides for both the user and also for the manufacturer benefits. The components are relatively easy to manufacture and assemble. However it will be appreciated that modifications can be made, without affecting the fundamental Operation of the apparatus would be changed.

A second embodiment the invention is in the <figref idrefs="S33">14</figref> - <figref idrefs="S38">19</figref> shown. It is less than those in the <figref idrefs="S20">1</figref> - <figref idrefs="S30">11</figref> shown embodiment preferred, but is still effective for providing the shield a needle or similar sharp instrument in response to the axial movement of the instrument. In this embodiment, the invention is used no end cap. will instead the spring directly from the flange <figref>24</figref> the syringe in place Office held.

how in <figref idrefs="S33">14</figref> shown is a device <figref>100</figref> provided the syringe <figref>12</figref>, A holder <figref>102</figref>, A shield <figref>104</figref> and a coil spring <figref>106</figref> having. The holder<figref>102</figref> contains a cylindrical body <figref>108</figref>. a cylindrical cavity for receiving the shield <figref>104</figref> defined. The particular configuration of the holder is not critical so long it is easy to handle by the user of the device and the Shield has in place. A radially extending flange<figref>110</figref> is close of the holder end provided. This end of the holder contains further a housing <figref>112</figref> to the slidably holding the flange <figref>24</figref> similarly Manner as in the first embodiment <figref>10</figref> the Invention was used. The housing<figref>112</figref> contains two opposing surfaces which the distance limit, which the syringe with respect can move the holder. The configuration of the housing may be modified in order to respond to Spritzenflansche various sizes and shapes.

The feather <figref>106</figref> presses against the proximal end of the shield <figref>104</figref> and against the pointing to the distal end surface of the syringe flange <figref>24</figref>, The proximal end of the shield is radially enlarged to form a collar <figref>114</figref> educated becomes. an annular stop element <figref>116</figref> is formed on the inner surface of the holder and before use of the syringe with the collar <figref>114</figref> in Engagement. <figref idrefs="S35">16</figref> shows the engagement of these Structures. The coils of the spring are in a substantially abutting relationship to each other when the syringe is in the position shown in this figure is.

The distal end of the holder has at least a first set of detents <figref>118</figref> on, which prevent the shield <figref>104</figref> the holder dissolves after the collar <figref>114</figref> the stop element <figref>116</figref> passes has been. These locks are made extending radially inward Appendages, with the collar <figref>114</figref> can come into engagement. While the Spring the shield in the protective position on the needle <figref>18</figref> considers, it is preferable that the shield permanently in this position to keep. One set of wedge-shaped detents <figref>120</figref> is accordingly on the inner surface of Holder provided. A second set of detents interfere moving past the collar <figref>114</figref> not, during the spring expands, but prevents retraction the shield, because the shoulder portions of the detents to the collar encounter. Either the holder or shield or both preferably have a certain degree of flexibility to an operation of the detents and also of the collar and the stop member to enable.

in the Operating the apparatus <figref>100</figref> substantially in the same manner as a conventional syringe used wherein initially the items in <figref idrefs="S35">16</figref> shown Arrangement. The user presses the plunger under the use of his thumb while the flanges of the holder by the index finger and the middle finger of the same Hand held. After the flask in an adjacent position the syringe barrel has been moved at the end, gives a user further exerted on the plunger Pressure axial movement of the syringe itself. Due to the abutting relationship the coils of the spring against each other, the spring forms actually a massive Connection between the syringe flange and the proximal end of the shield. Axial movement of the syringe accordingly causes a corresponding axial movement of the shield until the collar <figref>114</figref> about the stop element <figref>116</figref> moved out how in <figref idrefs="S37">18</figref> is shown. An extension of the spring causes the shield moved into an extended position as shown in <figref idrefs="S36">17</figref> shown is.

Of the Skilled person will understand and appreciate that other and additional revisions to the invention possible are, without thereby departing from the scope of the appended claims, the invention is not limited to the specific embodiments shown limited is.