1. Field of the Invention
This invention relates to a tip cap for closure of the opening of a liquid filled container, and more particularly, to a tip cap for a syringe.
2. Description of Related Art
Conventional syringes include a barrel having an open proximal end and an opposed distal end. A cylindrical wall extends between the ends and defines a substance retaining chamber. A tip, sometimes referred to as a luer, projects from the distal end of the syringe barrel and includes a narrow passage, which communicates with the substance-retaining chamber of the barrel. A plunger is inserted into the open proximal end of the syringe barrel for sliding fluid-tight engagement with the cylindrical chamber wall. Sliding movement of the plunger in a distal direction urges fluid in the chamber through the passage in the tip. Conversely, sliding movement of the plunger in a proximal direction draws fluid through the passage in the tip and into the chamber of the syringe barrel.
Such syringes may further include a needle assembly with a needle cannula having a proximal end, a pointed distal end and a lumen extending axially therethrough. The needle assembly commonly includes a hub which is securable to the syringe barrel for selectively placing the lumen of the needle cannula in fluid communication with the passage through the tip of the syringe barrel. The needle assembly may be removably or fixedly mounted to the tip of the syringe barrel.
Medications that are pre-filled into a syringe barrel must be sealed to prevent contamination or loss of the medication prior to use. Seals also prevent health care workers from being needlessly exposed to medications. Where a needle is not staked to the syringe body, the prior devices have included stoppers or closures mounted over the tip at the distal end of the syringe barrel, referred to as tip caps, to prevent leakage and to avoid contamination of the medication. When a pre-filled syringe is capped with a tip cap, it is especially important that a good seal be maintained. This is usually achieved by tightly affixing the tip cap to the syringe. However, when overly tightened the tip cap can be difficult to remove or may be damaged. Furthermore, a pre-filled syringe may be autoclaved after filling and capping to ensure a sterile package for the contents. The autoclaving procedure however, can also have the side effect of interactions between the tip cap to the syringe, thereby further increasing the difficulty in removing the cap.
The prior art tip cap is removed from the syringe tip shortly prior to usage of the syringe, and the hub of the needle assembly is securely engaged with the luer and/or luer collar or other mounting means adjacent the exposed tip of the syringe barrel. For example, the needle hub may be threadedly engaged within a luer collar such that the lumen of the needle cannula communicates with the exposed tip of the syringe barrel, such as with the configuration sold by the assignee herein under the trademark “Luer-Lok”.
Current tip caps used to seal the liquid opening of the syringe barrel, are typically a one-piece design having a circular cap wall design. The mechanical advantage of a screw-type threaded cap is translation of a rotational force to an axial force, resulting in wedging the sealing mechanism of the tip cap onto the luer of the container, and forming a tight seal due to the interference fit between the sealing mechanism and the luer. With the current tip caps, the torque required to attach and remove the tip cap is generated when the user applies a gripping force to the outside of the cap to rotate the cap on and off the syringe.
A problem associated with the prior art tip cap design has been the user must apply a gripping force to grasp the circular cap by exerting a force normal to the cap walls at the point of contact with sufficient force to hold the cap from slipping, as well as applying a twisting force (a torque) for rotating the cap about its axis. This can be difficult for some users who lack dexterity or strength especially considering the small size of the typical tip cap or in the case where the tip cap is in excessively tight engagement with the syringe barrel. The difficulty in using tip caps according to prior art design is that the user must exert forces on the tip cap at right angles to both grasp and rotate the tip cap simultaneously.
A need exists, therefore, for an improved syringe tip cap where the ability to attach and detach the tip cap is made easier by providing a tip cap that is easier to grip while simultaneously applying torque to rotate the tip cap. In particular, it would be advantageous to provide a tip cap with a non-circular shaped gripping surface that provides the user with a surface to grip the cap and apply force to the tip cap tangential to the axis of rotation without having to also apply a gripping force.
In contrast to the prior devices discussed above, it has been found that a tip cap which provides the user with enhanced mechanical advantage for rotating the cap in order to affix it to a syringe can be constructed in accordance with the present invention. Specifically, the tip cap of the present invention includes a non-circular cross-sectional shape that provides a gripping surface for providing the user with extra leverage to rotate the cap.
The present invention provides a syringe tip cap assembly for closing a syringe such as a pre-filled syringe barrel. The tip cap includes a tip cap body having a non-circular top wall, a base sealing surface and a depending shaft, which may be threaded, for attachment of the tip cap to a syringe. The opening and closing of a threaded tip cap is accomplished by imparting torque to the cap tangential to the axis of rotation to cause the cap to rotate and thereby open or close by engaging the helical threads of the cap and container to raise or lower the cap. The force imparted to the cap is applied by the user by gripping the perimeter of the cap.
The tip cap of the present invention makes it easier and more effective for the user to apply the rotational force needed to turn the cap and thus open and close it. The non-circular shaped gripping area provides a surface for the application of force directly tangential to the axis or rotation of the cap. The force is applied to the tip cap tangential to the axis of rotation at a distance from the axis. Therefore, the non-circular tip cap acts as a lever arm to multiply the force applied to the tip cap. In addition, because of the non-circular shape, the user need not apply a normal force to the sides of the cap in order to grip the cap as is the case with prior art designs.
An advantage of the tip cap of the present invention is that it provides the user with increased mechanical advantage for rotating the cap.
Another advantage of the tip cap of the present invention is that the outer surface of the tip cap contains features to enhance handling and grip for the user, and to provide a comfortable gripping surface that will not cut into the users fingers.
The present invention is therefore directed to a tip cap comprising a base portion having an upper surface and a lower surface, a body having a top wall with a non-circular cross-section extending from the upper surface, and a hollow shaft extending from the lower surface. attaching to a syringe barrel.
The various features, objects, benefits, and advantages of the present invention will become more apparent upon reading the following detailed description of the preferred embodiment(s) along with the appended claims in conjunction with the drawings, wherein like reference numerals identify like components throughout, and:
a respectively are perspective views of a tip cap according to different embodiments of the present invention with a textured top wall;
Referring now to the drawings,
It should also be noted that one or more outwardly extending nubs or tabs 51 may be formed extending in cantilevered fashion from the edge of sealing base 16 to facilitate handling of the tip cap 10 according to the present invention by machinery. The nubs or tabs 51 allow machinery, such as “forgiving” machines to handle the tip cap 10 without engaging the gripping surface 50. Accordingly, a more straightforward machine arrangement to engage nubs or tabs 51, may be utilized than if the gripping surface 51 needed to be handled. While four such nubs or tabs are shown in
As shown in
Turning now to
Turning now to
In
More particularly, a tip cap is opened or closed by imparting a force to the tip cap sufficient to overcome the forces holding it in place on the helical threads of the cap and the complementary container, or other complementary connection configuration, whereby the cap is moved from either an open or a closed position by the rotation of the cap. The forces to rotate the threaded cap are applied tangential to the axis of rotation of the cap at a distance from the axis of rotation. As shown and described in
In contrast, the tip cap 10 according to the present invention, has an elongated gripping portion that provides the user with a lever arm to easily rotate the tip cap 10. Preferably, as depicted in
Rotational force may be used to remove the tip cap 10 even where a threaded connector is not provided for a syringe body. For example, the tip cap 10 can be twisted off of a luer to which it is mounted with a slip luer connection. The torque advantage described above, therefore, is as beneficial in this context, and similar contexts, as well.
The tip cap 10 of the invention may be made of a clear molded thermoplastic material so that the syringe tip may be readily viewed through the tip cap. Representative materials include, for example, polyethylene, polypropylene, and polyvinyl chloride. Although it is within the purview of the invention to provide tip caps which are transparent, it is also within the purview of this invention to provide tip caps which are color coded.
While the tip cap 10 of the present invention has been particularly described with respect to a preferred embodiment having a non-circularly elliptical shaped top wall 14, it should be apparent to one skilled in the art and from the disclosure provided herein that various alternate embodiments of the tip cap top wall 14 are contemplated by, and within the scope and spirit of the present invention. For example, the tip cap 10 may alternately include modifications such as alternate shapes or additional gripping elements to enhance torque generation. Alternate top wall 14 shapes can include, in addition to the non-circular elliptical shape of the preferred embodiment, oval shapes, polygonal shapes, such as squares and rectangles, and other non-circular shapes that provide the desired torque-reducing characteristics of the tip cap 10 of the present invention. Furthermore, additional alternate embodiments may include the tip cap top wall 14 having radially projecting structures arranged about the top wall 14. The projecting structures provide the user with an extended gripping surface 50, which acts as a lever arm to impart additional torque to the tip cap 10 when rotated by the user, as described above in connection with the embodiments of
The gripping elements may alternately be arranged in such a way as to provide the user with an easily gripped surface for imparting torque to the tip cap 10. The gripping element may take various alternate forms, for example, the tip cap 10 may be made with a star shape or having radially extending structures arranged around the perimeter of the tip cap 10. Alternately, the tip cap 10 can be shaped having a square or rectangular shape.
As will be recognized by one skilled in the art and from the disclosure provided herein, various configurations are within the scope and spirit of the present invention. By way of non-limiting examples and turning to
Turning now to
While the preferred embodiments of the present invention have been described so as to enable one skilled in the art to practice the device of the present invention, it is to be understood that variations and modifications may be employed without departing from the concept and intent of the present invention as defined in the following claims. For example, the top wall shape can be varied by increasing or decreasing the major and minor axes. Alternately, the top wall could be other non-circular shapes, which are preferably elongated, such as, for example, rectangular. Accordingly, the preceding description is intended to be exemplary and should not be used to limit the scope of the invention. The scope of the invention should be determined only by reference to the following claims.
This application is a continuation-in-part of U.S. Design Application No. 29/180,313, filed on Apr. 22, 2003, now U.S. Pat. No. D, 493,526 which is incorporated by reference herein.
Number | Name | Date | Kind |
---|---|---|---|
2585527 | Adams | Feb 1952 | A |
3344786 | Berg et al. | Oct 1967 | A |
3664338 | Knox et al. | May 1972 | A |
3718139 | Hanford | Feb 1973 | A |
3777655 | Ainsworth | Dec 1973 | A |
3916894 | Cloyd | Nov 1975 | A |
3986645 | Baldwin et al. | Oct 1976 | A |
4006837 | Gates et al. | Feb 1977 | A |
4043334 | Brown | Aug 1977 | A |
4202334 | Elson | May 1980 | A |
4238042 | Hatakeyama et al. | Dec 1980 | A |
4286591 | Raines | Sep 1981 | A |
4402420 | Chernack | Sep 1983 | A |
4535906 | Rowekamp | Aug 1985 | A |
4571242 | Klein et al. | Feb 1986 | A |
D302206 | McAlister et al. | Jul 1989 | S |
4898588 | Roberts | Feb 1990 | A |
4926915 | Deussen et al. | May 1990 | A |
4932937 | Gustavsson et al. | Jun 1990 | A |
4979945 | Wade et al. | Dec 1990 | A |
5108889 | Smith et al. | Apr 1992 | A |
D327318 | Dudar et al. | Jun 1992 | S |
5322515 | Karas | Jun 1994 | A |
5634496 | Grabner, Jr. | Jun 1997 | A |
D381965 | Atkinson | Aug 1997 | S |
5725507 | Petrick | Mar 1998 | A |
5782804 | McMahon | Jul 1998 | A |
5807345 | Grabenkort | Sep 1998 | A |
5925029 | Jansen et al. | Jul 1999 | A |
5954957 | Chin-Loy et al. | Sep 1999 | A |
5992656 | Dujardin et al. | Nov 1999 | A |
D447797 | Odell et al. | Sep 2001 | S |
D447799 | Jun | Sep 2001 | S |
6309375 | Glines et al. | Oct 2001 | B1 |
D457954 | Wallace | May 2002 | S |
6695829 | Hellstrom et al. | Feb 2004 | B2 |
6875205 | Leinsing | Apr 2005 | B2 |
20020174864 | Alchas | Nov 2002 | A1 |
20040097882 | DiBiasi et al. | May 2004 | A1 |
20040116869 | Heinz et al. | Jun 2004 | A1 |
Number | Date | Country |
---|---|---|
2 570 055 | Mar 1986 | FR |
Entry |
---|
Communication Pursuant to Article 96(2) EPC for European Patent Application No. 03 773 313.6-1257 dated May 22, 2007 (6 pages). |
Number | Date | Country | |
---|---|---|---|
20040215148 A1 | Oct 2004 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 29180313 | Apr 2003 | US |
Child | 10691385 | US |