Abstract:
A fluid infusion system including a pocketable pump housing with a reservoir cavity with helical coupling features. The system further has a reservoir with an open end that is removable from the reservoir cavity. A removable cap coupled to the housing is also included in the system. The cap has corresponding coupling features, an exterior surface and a tab. The corresponding coupling features couple the cap to the housing while the tab is a ridge that extends away from the exterior surface. The tab has a port to accommodate flow from the reservoir and the port defines an axis of rotation such that torque applied to the tab about the axis of rotation disengages the coupling between the cap and the housing. The system further has a removably coupled guard with a slot defined to immobilize rotation of the tab about the axis of rotation.

Description:
FIELD OF THE INVENTION 
       [0001]    Embodiments of the invention relate to diabetes management systems and, more particularly, to securing a fluid reservoir within a portable infusion device. 
       BACKGROUND OF THE INVENTION 
       [0002]    Infusion devices and glucose monitoring systems are relatively well known in the medical arts, particularly for use monitoring blood glucose levels and delivering or dispensing a prescribed medication to a user. In many cases, the user suffers from diabetes—a disease in which the body does not produce or properly use insulin. Approximately 13 million people in the United States have been diagnosed with some form of diabetes. Type 1 diabetes results from the body&#39;s failure to produce insulin. Type 2 diabetes results from insulin resistance in which the body fails to properly use insulin. In order to effectively manage and/or control the disease, diabetics must closely monitor and manage their blood glucose levels through exercise, diet and medications in addition to supplying their body with appropriate amounts of insulin based on daily routines. In particular, both Type 1 and Type 2 diabetics rely on insulin delivery and blood glucose monitoring systems to control diabetes. 
         [0003]    External infusion devices have been used to deliver medication to a patient as generally described in U.S. Pat. Nos. 4,562,751; 4,678,408; 4,685,903; 6,554,798, and 6,551,276 which are specifically incorporated by reference herein. In recent years, continuous glucose monitoring systems have been developed utilizing the latest sensor technologies incorporating both implantable and external sensors, as generally described in U.S. Pat. No. 5,391,250 entitled “Method of Fabricating Thin Film Sensors”, U.S. Pat. No. 6,484,046 entitled “Electrochemical Analyte Sensor,” and U.S. Pat. Nos. 5,390,671, 5,568,806 and 5,586,553, entitled “Transcutaneous Sensor Insertion Set,” all of which are specifically incorporated by reference herein. Newer systems deliver the preciseness of finger stick measurements coupled with the convenience of not having to repeatedly prick the skin to obtain glucose measurements. These newer systems provide the equivalent of over 200 finger stick readings per day. Additionally, continuous glucose monitoring systems allow physicians and patients to monitor blood glucose trends of their body and suggest and deliver insulin based on each patient&#39;s particular needs. Accordingly, physicians and medical device companies are always searching for more convenient ways to keep diabetic patients aware of their blood glucose levels throughout the day. 
         [0004]    Diabetic patients utilizing infusion therapy and continuous glucose monitoring systems depend on extremely precise and accurate systems to assure appropriate blood glucose readings and insulin delivery amounts. Furthermore, as younger diabetic patients and diabetic patients with active lifestyles embrace infusion therapy it is imperative to ensure the infusion devices and sensors are robust and reliable. 
       SUMMARY OF THE DISCLOSURE 
       [0005]    In one embodiment a fluid infusion system is disclosed. The fluid infusion system includes a pump housing that has a reservoir cavity and is designed to be pocketable. The reservoir cavity has a rim and helical coupling features formed on an interior face of the reservoir cavity. The fluid infusion system further has a reservoir that is removable from the reservoir cavity and the reservoir also has an open end. A removable cap coupled to the pump housing is also included in the fluid infusion system. The cap has corresponding coupling features, an exterior surface and a tab. The corresponding coupling features are defined to couple the cap to the pump housing while the tab is defined as a ridge that extends away from the exterior surface. The tab further has a port to accommodate fluid flow from the reservoir where the port defines an axis of rotation such that torque applied to the tab about the axis of rotation disengages the coupling between the cap and the pump housing. Further included in the infusion system is a guard that is removably coupled to the pump housing. The guard has a slot defined to immobilize rotation of the tab about the axis of rotation. 
         [0006]    In another embodiment a system to retain a fluid medication reservoir within a medication pump housing is disclosed. The system includes a pump housing that is pocketable having a reservoir cavity that has a rim and helical coupling features. The helical coupling features formed on an interior face of the reservoir cavity and having a dimple formed on the rim. The system further includes a reservoir that has an open end and is removable from the reservoir cavity. A cap that is removably coupled to the pump housing is also included in the system. The cap has corresponding coupling features, an exterior surface, and a tab. The corresponding coupling features are defined to couple the cap to the pump housing, and include a snap defined on an edge of the cap that removably interfaces with the dimple on the pump housing. The tab is defined as a ridge that extends away from the exterior surface and the tab has a port to accommodate fluid flow from the reservoir. The port through the tab defines an axis of rotation such that torque applied to the tab about the axis of rotation disengages the coupling between the cap and the pump housing. The system further includes a guard that is removably coupled to the pump housing. The guard has a slot that is defined to immobilize rotation of the tab about the axis of rotation. Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings which illustrate, by way of example, various features of embodiments of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    A detailed description of embodiments of the invention will be made with reference to the accompanying drawings, where like numerals designate corresponding parts or cross-sections in the several figures. 
           [0008]      FIG. 1  is an exemplary illustration of a fluid infusion system that includes a pump, an insertion set and a sensor, in accordance with embodiments of the present invention. 
           [0009]      FIGS. 2A and 2B  are exemplary perspective views of a portion of the pump housing, with guard installed and removed respectively, in accordance with embodiments of the present invention. 
           [0010]      FIG. 2C  is a top view illustration of a portion of the pump housing with a guard installed over the cap, in accordance with embodiments of the present invention. 
           [0011]      FIG. 3  is a perspective view of the pump illustrating features on the pump housing that are engaged by the guard, in accordance with embodiments of the present invention. 
           [0012]      FIGS. 4A and 4B  are close-up perspective views illustrating features of the pump housing and the guard, in accordance with embodiments of the present invention. 
           [0013]      FIGS. 5A-5D  are additional views of the pump housing and the guard, in accordance with embodiments of the present invention. 
           [0014]      FIGS. 6A and 6B  are exemplary perspective illustration showing features that prevent the guard from being installed onto the pump in a reverse orientation, in accordance with embodiments of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0015]      FIG. 1  is an exemplary illustration of a fluid infusion system  10  that includes a pump  100 , an insertion set  106  and a sensor  112 , in accordance with embodiments of the present invention. Mechanical, electrical and software elements of the pump  100  are contained within a pump housing  110 . The pump includes a reservoir  104  that is removable from a reservoir cavity within the pump housing  110 . The reservoir  104  may be filled with a fluid that can be dispensed from the pump  100  to the insertion set  106  via tubing  108 . A cap  102  interfaces with both the pump  100  and the reservoir  104  to connect the tubing  108  with the reservoir  104 . 
         [0016]    The sensor  112  is an assembly that includes a subcutaneous sensor, a power supply and a radio to transmit data acquired by the sensor to the pump  100 . The pump  100  is configured and programmed to be in wireless communication with the sensor  112 . For additional information regarding the pump  100  see U.S. Pat. 6,554,798 by Mann et al., for additional information regarding the connection between the reservoir  104  and the insertion set  106  see U.S. Pat. No. 6,585,695 by Adair et al., furthermore, for additional information regarding the sensor  112  see U.S. Pat. No. 5,568,806 by Cheney et al., U.S. Pat. No. 6,484,045 by Holker et al., and U.S. Pat. No. 7,003,336 by Holker et al., all of which are incorporated by reference herein. For additional information regarding the use the sensor  112  with a monitor or pump, please see U.S. Pat. No. 6,809,653 by Mann et al. which is incorporated by reference herein. 
         [0017]      FIGS. 2A and 2B  are exemplary perspective views of a portion of the pump housing  110 , with guard  200  installed and removed respectively, in accordance with embodiments of the present invention. The guard  200  interfaces with features on the pump housing  110  and the cap  102 . The cap  102  has an exterior surface  206  and a tab  202 . In one embodiment the tab  202  is defined as a ridge that extends away from the exterior surface  206 . The tab  202  includes a port  204  that can accommodate tubing (not shown). A user can grasp the tab  202  in order to apply a torque to the cap  102  in order to remove the cap  102  and attached reservoir from the pump housing  110 . The embodiment illustrated in  FIGS. 2A and 2B  should not be construed as limiting. 
         [0018]    As will be described in more detail in the description of  FIG. 3 , the pump housing  110  has a rim  208  that includes and enables features that interface with the guard  200 . In one embodiment, the rim  208  of the pump housing  110  is formed from a separate part that is mated and permanently affixed to the pump housing  110 . Methods of permanently affixing the rim  208  to the pump housing  208  include, but are not limited to the use of insert molding, ultrasonic welding, adhesives or the combination thereof. In other embodiments, the rim  208  and associated features are created during the forming of a one-piece pump housing. Regardless of the whether the rim  208  is formed or installed, the pump housing  110  includes a rim  208  that facilitates the installation and retention of the guard  200 . 
         [0019]      FIG. 2C  is a top view illustration of a portion of the pump housing  110  with a guard  200  installed over the cap  102 , in accordance with one embodiment of the present invention. As illustrated, the guard  200  includes arms  210   a  and  210   b  that are connected. Defined between the arms  210   a  and  210   b  is a slot  212 . As illustrated, when the cap  102  in installed on the pump housing  110  and a guard  200  in placed over the cap  102 , the slot  212  captures the tab  202  to prevent rotation of the tab  202 . 
         [0020]      FIG. 3  is a perspective view of the pump  100  illustrating features on the pump housing  110  that are engaged by the guard (not shown), in accordance with embodiments of the present invention. As illustrated, features on the pump housing  110  that are engaged by the guard include, but are not limited to, a rib  300 , a nub  302   a , and detents  304   a  and  304   d . In one embodiment the nub  302   a  is formed entirely on the rim  208 . Conversely, the rib  300  can be formed when the rim  208  is permanently affixed to the case housing  110 . Likewise, detents  304   a  and  304   d  can also be formed when the rim  208  is affixed to the pump housing  110 . Additional features on the pump housing  110  will be discussed below when the various views of the pump housing  110  reveal the different features. 
         [0021]      FIGS. 4A and 4B  are close-up perspective views illustrating features of the pump housing  110  and the guard  200 , in accordance with embodiments of the present invention. Arms  210   a  and  210   b  terminate away from the joint with snaps  400   a  (not shown) and  400   b  respectively. Each snap  400   a  and  400   b  have a corresponding detent  304   a  and  304   b  (not shown) formed on the case housing  110 . Additionally, snap  400   d  is formed on arm  210   a  near the joint between arms  210   a  and  210   b . Similarly, though not shown in  FIGS. 4A and 4B , snap  400   c  is formed on arm  210   b . As previously discussed, the detents  304   a  and  304   b  can be formed during the fabrication of the case housing  110  or when the rim  208  is affixed to the case housing. In the exemplary embodiment shown in  FIG. 4B  the snap  400   d  has a tapered face  402 . While not shown, a corresponding snap  400   c  located on arm  210   b  can also include a tapered face. The use of the tapered face  402  facilitates the installation of the guard  200  onto the case housing  110 . Specifically, the tapered face  402  enables the use of a lower amount of force necessary to pass snap  400   d  over the rim  208  in order to engage an corresponding detent. 
         [0022]      FIGS. 5A-5D  are additional views of the pump housing  110  and the guard  200 , in accordance with embodiments of the present invention.  FIG. 5A  is a profile view of the arm  210   a  and illustrates how detent  304   a  is engaged by a snap on the terminated arm  210   a . Likewise, snap  400   c  is shown engaged in detent  306   a . Also visible in  FIG. 5A  is the profile contour of face  500 . The contour of face  500  in conjunction with the placement of snaps  400   c  enables the repeated removal of guard  200  from the pump housing  110 . The face  500  allows user to apply an upward force that can disengage snap  400   c  and  400   d  (not shown) from detent  306   a  and  306   b  (not shown). 
         [0023]      FIGS. 5B and 5C  are exemplary illustrations where the guard  200  has been made translucent in order to show how the guard  200  interfaces with the pump housing  110 , in accordance with embodiments of the present invention. As  FIG. 5B  illustrates the arm  210   b  side of the pump housing  110 , snap  400   c  and detent  306   b  are visible.  FIGS. 5B and 5C  also illustrate how the guard  200  includes a recess  502  that interfaces with the rib  300  of the pump housing  110 . The recess  502  and the rib  300  work in conjunction with the slot  212  ( FIG. 2C ) to allow the guard to resist torque applied to the tab  202 . The use of both the slot and the rib  300  to prevent rotation of the tab  202  is merely one embodiment. In other embodiments only the slot formed between arms  210   a  and  210   b  may be used to counteract rotation of the tab. Similarly, in another embodiment, only the rib  300  and recess  502  may be used to lock the tab  202  by preventing rotation Likewise, additional features can be used to immobilize rotation of the tab in furtherance of either the slot and the rib. 
         [0024]      FIGS. 5C and 5D  provide an exemplary illustration of the removal of the guard  200  from the pump housing  110 , in accordance with embodiments of the present invention. In one embodiment to avoid inadvertent removal, the guard  200  is securely attached to the pump housing  110  and requires two steps to remove the guard  200 . To initiate removal of the guard  200 , a force F 1  is applied to both arms  210   a  and  210   b , as illustrated in  FIGS. 5C and 5D . Application of force F 1  causes the arms  210   a  and  210  be spread. Force F 1  further pushes the guard  200  toward the rib  300 .  FIG. 5D  illustrates the second step to remove the guard  200 , the application of force F 2  on face  500  ( FIG. 5A ). The application of force F 1  can help disengage snap  400   c  ( FIG. 5B ) and snap  400   d  ( FIG. 4A ) thus allowing force F 2  to remove the guard  200  from the pump housing  110 . As the guard  200  can be installed to prevent children from accidentally removing the cap  102 , a two step method (the application of F 1  and F 2 ) can make it more difficult for children to remove the guard  200 . If F 2  is not applied after application of F 1  the geometry of the legs is such that the Guard reseats itself. 
         [0025]    While it may be beneficial in some instances to have a two step removal process, it should not be construed as required. In other embodiments, a one step removal process may be used while in other embodiments three or more steps may be desired to ensure the guard is difficult to remove. Additionally, for two step removal, the steps outline above should not be considered restrictive as other embodiments of the guard  200  may use a different combination of forces other than F 1  and F 2 . 
         [0026]      FIG. 5C  further provides an illustration of additional retention features on both the pump housing  110  and the cap  102 , in accordance with embodiments of the present invention. The cap  200  includes snaps  504   a  and  504   b  that are formed on an outer edge of the cap  200 . Included on an interior face of the rim  208  are dimples  506   a  and  506   b  that correspond to the snaps  504   a  and  504   b . While  FIG. 5C  illustrates the use of two snaps  504   a  and  504   b , other embodiments can use fewer or more snaps. Furthermore, while the snaps  504   a  and  504   b  are illustrated substantially opposite of each other, other configurations could be used to incorporate fewer or greater number of snaps. For example, snap configurations could include, but are not limited to three equally spaced snaps, four equally spaced snaps, and even a single snap. Still other snap configuration could include snaps that are not equally spaced. In embodiments were the cap  102  utilizes fewer or more snaps that illustrated in  FIG. 5C , the rim would have a corresponding number of dimples to accommodate the snaps on the cap. 
         [0027]      FIGS. 6A and 6B  are exemplary perspective illustration showing features that prevent the guard  200  from being installed onto the pump  100  in a reverse orientation, in accordance with embodiments of the present invention. In  FIG. 6A  the guard  200  is shown in a reverse orientation such that the rib  300  is not aligned with the recess  502  ( FIG. 5C ) of the guard  200 . Nubs  302   a  and  302   b  are included on the rim  208  to prevent installation of the guard  200  in this orientation. The nubs  302   a  and  302   b  are designed to interfere with the guard  200  and prevent the guard  200  from snapping onto the pump housing  110 . In other embodiments, the nubs  302   a  and  302   b  are replaced with a rib that extends the surface of the rim  208  to a height equivalent to the nubs  302   a  and  302   b .  FIG. 6B  is an exemplary illustration showing how the termination of arms  210   a  and  210   b  create an interference  600  with the pump housing  110  in order to prevent the guard  200  from being installed in the reverse orientation. 
         [0028]    While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. 
         [0029]    The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.