Patent Publication Number: US-7914335-B2

Title: Strip connectors for measurement devices

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 12/175,279, filed on Jul. 17, 2008, which application is incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. The Field of the Invention 
     Embodiments of the invention relate to strip connectors in measurement devices. More particularly, embodiments of the invention relate to strip connectors for use with measurement devices that are substantially impervious to liquid or other contaminants or that are replaceable or disposable. 
     2. The Relevant Technology 
     Diabetes is a disease that afflicts many people. One of the tools used in diabetes management is a measurement device, whose primary purpose is to measure the blood glucose level of a person from a sample of blood. The process of using a measurement device is not overly complicated and it is often performed several times a day. 
     After inserting a test strip into a port of the measurement device, a user may lance his or her finger to obtain a small sample of blood. The blood sample is then placed onto the test strip and the measurement device analyzes the blood sample. The measurement device typically displays a blood glucose level from the analysis. 
     In order to ensure that an accurate measurement is being generated, it is necessary to keep the measurement device free from contamination. There are instances where the port becomes contaminated with blood, for example. When this occurs, the performance of the measurement device suffers and the user is no longer assured of an accurate result. As a result, the user is likely required to purchase a new measurement device. A user can be inconvenienced because of the inaccurate results and the need to purchase a new device. 
     BRIEF SUMMARY OF THE INVENTION 
     Embodiments of the present invention relate to strip connectors on measurement devices or for use with measurement devices. Embodiments of the invention include strip ports that are corrosion resistant, washable, impervious to liquid ingress, dust proof, conductive, and/or replaceable. In one embodiment, the measurement device includes a case that has a first end. A strip connector may be disposed in the first end or other portion of the case. The strip port includes contacts that extend out from the first end. The case may be formed such that an interface between the case and the contacts forms a barrier that is substantially impervious to liquids. The interface allows the strip connector and the contacts to be cleaned and allows the contacts to be kept free from contaminants. This extends the mean time before failure (MTBF) of the device because the strip connector can be cleaned. 
     In certain embodiments, the port is configured to be replaceable. In this example, the device includes a receptacle for receiving the port. The port may include a first portion having a first electrical interface. The first electrical interface is typically configured to interface with the device. The first portion of the device also includes a second electrical interface. 
     The port may also include a second portion. A third electrical interface may be configured to detachably and electrically connect with the second electrical interface. This allows the second portion to be removed from the first portion and replaced if contaminated or for any other reason. The second portion also includes a strip port configured to receive a test strip. The port then provides an electrical and physical connection between the measurement device and the test strip. 
     A disposable port or a port with a disposable portion also increases the MTBF of the device. Also, a disposable port allows the second portion to be selected to accommodate different test strip form factors. 
     These and other advantages and features of the present invention will become more fully apparent from the following description and appended claims, or may be learned by the practice of the invention as set forth hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  illustrates a view of a measurement device including a strip connector that makes the strip interface cleanable; 
         FIG. 2  illustrates a perspective view of a measurement device with a strip connector; 
         FIG. 3  illustrates one embodiment of contacts included in a strip connector; 
         FIG. 4  illustrates another embodiment of contacts included in a strip connector; 
         FIG. 5  illustrates another embodiment of contacts included in a strip connector; 
         FIG. 6  illustrates a device with spring arm connectors connected with a test strip; 
         FIG. 7  illustrates a top view of a device with contacts that is electrically connected with a test strip; 
         FIG. 8  illustrates another embodiment of a device with pin contacts that interface with corresponding sockets on a test strip; 
         FIG. 9  illustrates a top view of pin contacts in a strip connector; 
         FIG. 10  illustrates a perspective view of a device that uses a disposable strip port; 
         FIG. 11  illustrates a side view of an end of the device including the electrical interface that receives the disposable port; 
         FIG. 12  illustrates a top view of a disposable port that interfaces with a device and with a test strip; 
         FIG. 13  is a perspective view of a disposable port that includes a separable portions such that one portion interfaces with the measurement device and another portion interfaces with a test strip; 
         FIG. 14  illustrates a perspective view of one embodiment of a portion of the disposable port that provides an electrical interface for a test strip; 
         FIG. 15  illustrates an end view of the disposable port including the test strip interface; 
         FIG. 16  illustrates electrical connections between the device and the test strip through the disposable port; and 
         FIGS. 17A and 17B  illustrate additional structure for associating the strip port with a measurement device. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the invention relate to electrical interfaces in measurement devices. Measurement devices often have electrical interfaces that allow them to electrically connect with another device or apparatus and perform an analysis of an analyte. A device that measures blood glucose levels, for example, includes electrical interfaces that allow the device to measure the blood glucose level from a small blood sample. 
     Embodiments of the invention relate to systems and methods that can improve the mean time before failure (MTBF) in measurement devices. This has the benefit of providing a user with a device that lasts longer and also ensures that the measurements or analysis performed by the device are more accurate over time. 
     More specifically, embodiments of the invention relate to strip connectors or strip ports that can be cleaned and/or replaced. The ability to clean or replace a strip port can prevent the device from experiencing problems often associated with port contamination. Blood and other contaminants, for example, can often contaminate a port and make the device unusable or result in inaccurate analysis. A port that can be cleaned or replaced without affecting the operation of the device thus increases the MTBF. 
     One embodiment thus relates to an insert molded strip connector configuration that prevents the ingress of liquid or other contaminant. The molded strip connector can be corrosion resistant, washable, water proof, dust proof, and highly electrically conductive. In another embodiment the port or at least a portion of the port is disposable. A disposable port allows the device to adapt to different test strip form factors by selecting the appropriate port replacement and also allows the device to continue to function when the port is contaminated by simply replacing the contaminated port. 
       FIG. 1  illustrates a top view of one embodiment of a measurement device used to analyze an analyte. The measurement device  100  typically includes a display  102  and a user interface  104 . The display  102  can be used to provide instructions or results to the user related to the measurement of the blood glucose level in a sample of blood. The user interface  104  allows a user to perform various functions, including starting the analysis, turning the device on/off, and the like. 
       FIGS. 1 and 2  also illustrate an example of a strip connector  110 . The strip connector  110 , in this example, includes a plurality of contacts  112 . The contacts  112  provide a physical and/or electrical interface to an appropriately configured test strip or test strip module. In this example, the case  108  of the device  100  may be molded around the contacts  112 . By molding the case  108  of the device  110  around the contacts, the interface between the case  108  and the contacts  112  becomes impervious to contamination, including liquid contamination (e.g., water, blood, etc.). The interface between the case  108  and the contacts  112  then becomes waterproof or at least sufficiently waterproof to allow the device  100  or at least the strip connector  110  to be washed. The ability to wash the device  100  or at least the strip connector  110  makes the device  100  substantially or completely corrosion resistant, washable, waterproof and dustproof. Contaminants can be removed or cleaned from the device without affecting the device  100 . 
     The contacts  112  are usually conductive and may be gold plated to improve the conductivity of the contacts  112 . The contacts  112  may also be formed of high strength steel to protect the contacts, which are exposed and extend out of the case  108  of the device  100 . In other embodiments, the contacts may be formed from impregnated polymers, beryllium copper, phosphor bronze, titanium, nickel plated, tin plated or any combination thereof. In alternative embodiments, the contacts may be any material that provides the proper conductivity where necessary. 
     The contacts  112  can be arranged in a plurality of different configurations. The contacts can be arranged in one or more rows and/or columns on the surface  120 . The contacts  112  can be arranged to connect with different sides of the printed circuit board (or other connector) inside the device  100 . Further, the contacts  112  can be bent or shaped to connect with a test strip and provide the electrical and/or mechanical connection between the device  100  and the test strip. As discussed more fully herein the device  100  can be configured with various types of contacts that permit the device to interface with test strips of different form factors. In addition, other structures may extend out of the surface  120  to provide mechanical structure to secure the test strip. 
       FIG. 3  illustrates a side view of a device  100  including the strip port  110 . In this example, the strip port  110  extends out of the device  100  through the surface  120  and the interface between the surface  120  and the contacts  112  is sealed or substantially sealed to prevent ingress of liquid or other contaminant. The contacts  112  typically pass through the surface  120  of the device  100  and include a connector  114  to the printed circuit board  106 . The connector  114  may be a bond wire or other connection to form a conductive path between the printed circuit board  106  and the contacts  112 . The contacts  112 , in this embodiment, are pin type contacts. 
       FIGS. 4 and 5  illustrate additional embodiments of the contacts  112 .  FIG. 4  illustrates a clip pin  114  while the contact depicted in  FIG. 5  is a spring arm  116 . Each type of contact  112  enables physical and/or electrical contact with a corresponding test strip in a different way and may accommodate different form factors. In each example, the contacts  112  pass through the surface  120  of the device  100  and electrically connect with a printed circuit board or other circuitry inside the device. The surface  120  has been formed around the contacts  112  to provide a barrier that allows the contacts  112  to be cleaned or washed. 
       FIG. 6  illustrates a side view of the device  100  connected with a test strip  150 . In this example, the device  100  includes spring arms  116  that extend out of the surface  120 . When the strip  150  is inserted into the spring arms  116 , the spring arms  116  may separate and exert a force towards the test strip  150  to hold the test strip in place physically and to provide an electrical connection between the spring arms  116  and the test strip  150 . In  FIG. 6 , the portion  118  of the spring arms  116  inside the device  100  connect with the printed circuit board  106  on both sides in this example, although there is no requirement that each portion of each of the spring arms  116  or of the contacts in general be used to establish an electrical connection. 
     The case  108  of the device  100  has been formed, such as by injection molding, to form a surface  120  that encloses the portion  118  of the spring arms  116  (or other contact) inside of the device  100  while exposing the external portion of the spring arms  116  (or other contact). As a result, the interface between the spring arms  116  and the surface  120  is sealed or substantially sealed to prevent ingress of liquid such as blood or other contaminant from entering the device  100  and interfering with the operation or functionality of the device  100 . As a result of this interface, the spring arms  116  or other contact can be washed or cleaned in the event of contamination or for any other reason without interfering with the operation of the device  100 . 
       FIG. 7  illustrates a top view of the device  100  illustrated in  FIG. 6 . In this example, the spring arms  116  extend out of the surface  120  and are connected to the test strip  150 . A blood sample  156  is loaded on the test strip and contacts  156  and  158  are in contact with the spring arms  116 . In this example, the contact  158  is on one side of the test strip  150  while the contact  156  is on the other side of the test strip  150 . The spring arm configuration illustrated in  FIG. 7  enable contacts  158  and  156  of the test strip  150  to be on either side of the test strip. In some instances, some of the spring arms  116  may not be in electrical contact with the test strip  150 . 
       FIG. 8  depicts a perspective view of another embodiment of a molded strip connector. In this example, the device  100  includes pin contacts  112  that pass through a surface  120  of the device  100 . At least some of the pin contacts  112  encased or enclosed within the case  108  of the device  100  are electrically connected to the printed circuit board  106 . Because the contact pins  112  can be arranged in various configurations, such as rows and columns, the pin contacts  112  can connect to both sides of the printed circuit board  106 . 
     The test strip  160  illustrated in  FIG. 8  includes sockets  162  that are shaped and configured to cooperate with the pin contacts  112  to establish at least an electrical connection, but may also provide physical stability to the connection between the test strip  160  and the device  100 . The sockets  162  are mounted in a connection module  164  that routes the electrical connection of the sockets  162  to the strip  160  such that the device  100  can analyze any analyte located thereon. 
       FIG. 9  illustrates a top view a device with a test strip port.  FIG. 9  illustrates that the contacts  112  can be inserted into the sockets  162  to form a connection between the device  100  and the test strip  160 . When a sample is loaded in the space  166 , the connection established between the device  100  and the test strip  160  via the pin contact/socket connection, the sample can be analyzed. 
     Another embodiment of the invention relates to a disposable strip port. A disposable strip port enables the port or a portion thereof to be exchanged, by way of example and not limitation, for another port or portion thereof when the current port or portion thereof malfunctions or is contaminated.  FIG. 10  illustrates a perspective view of a measurement device  200 . The device  200  includes a display  202  and a user interface similar to the display and user interface illustrated in  FIG. 1 . The display  202  may be used to convey information including results (such as blood glucose level) on an analysis of an analyte such as a blood sample. 
     The device  200  includes a port  208  that is inset in a receptacle  206  formed in the device  200 . The receptacle  206  can be configured to receive a disposable or replaceable port  250 . As illustrated in  FIG. 10 , the disposable port  250  can be inserted into the receptacle  206  and connected both physically and electrically with the device  200  through the port  208 . The disposable port  250  includes a strip port  252  that is configured to receive the test strip  150 . When the port  250  is inserted into the receptacle  206 , the surface with the port  252  is often flush with the surface  214 , although other configurations are possible with respect to the position of the port  250  relative to the device  200 . 
       FIG. 11  illustrates a view of an end of the device  200 .  FIG. 11  illustrates that port  208  and the printed circuit board  212  (or other suitable interface) are disposed therein at the end of the receptacle  206 . The printed circuit board  212  may have traces  216  or other contacts on either side of the printed circuit board  212 . 
       FIG. 12  illustrates a top view of the device  200 , the port  250 , and a test strip  150 . In this example, the port  208  provides access to the contacts  216  of the printed circuit board  212 . The port  250  also includes corresponding contacts  254  that are configured to connect with the traces  216 . The contacts  254  may be spring arms, pins, and the like or any combination thereof. Further, the port  208  may be insert molded as previously described to provide an interface that is substantially impervious to contaminants. In this case, the port may be changeable to allow the device  200  to adapt to different form factors or to provide other functions according to the configuration of the port  250 . 
     In this example, the port  250  also has a strip receptacle  260  (an example of the strip port  252 ) or strip port disposed on a side opposite the contacts  254 , although the receptacle can be repositioned on any side of the port  250 . The test strip  150  may be inserted into the receptacle  260  and a sample of the test strip  150  may be analyzed when the port  250  is connected to the port  208 . 
     The port  250  in this example may include a first portion  256  and a second portion  258 . The portion  256  and the portion  258  can be one integrated port or may include portions that can be repeatedly separated and connected. As previously mentioned, the portion  258  can be replace with differently configured portions to provide a receptacle  260  that accommodates different test strip form factors. 
     The portion  256  may be configured to interface with the device  200  via the port  208 . The portion  256  may also include retention tabs  262  that interact with corresponding connectors  264  to connect at least the portion  256  with the device  200  physically. In one example, the portion  256  may permanently connect with the device  200 , while allowing the portion  258  to be disposable. Advantageously, a user can select differently configured portions  258  to adapt to different configurations of the test strips. This may allow a user not only to replace the port  250  or a portion thereof, but also utilize test strips of different form factors. 
       FIG. 13  illustrates a perspective view of one embodiment of a disposable port  250 . In this example, the port  250  includes a portion  256  that is configured to interface with test strips and a portion  258  that is configured to interface with a measurement device  200 . The portion  256  includes spring arms  254  that are configured to connect with traces on a printed circuit board as previously disclosed. Alternatively, the portion  258  may include pin contacts or other contacts that interface with corresponding structure on the port  208  of the device  200  to establish the requisite connection. 
     The portion  256 , in this example, includes a retention tab  262  that enables the port  250  to connect with the device  200  in a permanent or semi-permanent fashion. When connected to the device  200 , the tab  262  keeps the portion  256  in place while the portion  258  can be separated from the portion  256  and replaced with a new portion or simply cleaned. As previously noted, the portion  258  can have multiple configurations to enable connectivity with different test strip form factors. 
     The port  250  includes a guide member  264 , in this embodiment, that interacts with corresponding rail structure on the device  200  to facilitate insertion of the port  250  onto the device  200 . The cooperation of the guide member  264  and the rail structure can ensure that the port  250  is properly aligned with the port  208  during insertion and can also prevent damage to the contacts during both insertion and/or removal of the port  250 . This can prevent damage to the spring arms  264  and ensure that a proper connection is made between the port and the device. 
       FIG. 14  illustrates a perspective view of one embodiment of the portion  258 . The portion  258  includes pins  266  that are used to connect with corresponding structure in the portion  256 . The pins  266  may provide a friction fit with the corresponding structure to retain the connection between the portion  256  and the portion  258 . 
       FIG. 15  illustrates a view of a test port or receptacle  260  of the portion  258 . In this example, the portion  258  includes a receptacle  260  configured to receive a test strip. Contacts  270  are disposed inside the port and arranged to make at least electrical contact with the test strip in order to allow analysis of the blood sample on the strip. 
       FIG. 16  depicts a side view the device  200  with a disposable port  250  connected thereto.  FIG. 16  illustrates the spring arms  264  inside of the portion  256 . On the device side, the spring arms extent out of the port  250  and make contact with the printed circuit board  212  inside the device  200 . The opposite end of the spring arms  264  form sockets  272 . The sockets  272  are configured to receive and electrically connect with the pins  266  that extend out of the portion  258 . The pins  266  also include contacts  270  (illustrated as spring arms in this example) inside of the portion  258  that are configured to electrically connect with a test strip  150  when the test strip inserted in the receptacle or port  260 . 
     As previously stated, the portion  258  can be configured to adapt to multiple strip form factors. As a result, the portion  258  may also include contacts  270  that are configured as pins, plugs, sockets, clips, and the like or any combination thereof. The interface between the portion  256  and  258  allows at least the portion  256  to be replaceable when ever it begins to fail or is contaminated or for any other reason. Further, the electrical connections between the device  200 , the portion  256 , the portion  258 , and the test strip  150  can take various forms including, but not limited to, pin contacts, clip pins, spring arms, and the like or any combination thereof. In this example, the contacts or pins illustrated for the portions  256  and  258  cooperate to establish electrical connects. 
       FIGS. 17A-B  illustrates examples of the connections or associations between the port  250  and the device  200 .  FIG. 17A  illustrates that the connection between the port and the device may include a latch  282  that interfaces with a receptacle  280  to secure the portion  258  to the device  200 . The receptacle  280  and latch  282  cooperate to provide a connection. A release  284  may also be included in the device  200  that releases the latch  282  from the receptacle  280 . As a result, the connection illustrated in  FIG. 17A  can be permanent or semi-permanent. 
       FIG. 17B  illustrates another interface or connection between the device  200  and the port  250 . In this example, the device may include sockets  286  that have an opening adapted to receive the ball  288  connected to the port  250 . The ball  288 , when snapped into the socket  286 , expands the socket  286  to allow the ball  288  to enter the socket  286 . Once the ball is inserted, the socket contracts to establish the connection. As a result, a force is required to insert the ball  288  into the socket. A similar force may be required to release the connection illustrated in  FIG. 17B . In these examples, the connection may be semi-permanent and ensures that the electrical connection is maintained. 
     In other embodiments, the connection between the port  250  and the device  200  (or between the contact pins  266  and sockets  272 ) may include a press fit or a friction fit. For instance, the port  250  may be slightly wider than the receptacle  206 . As the port  250  is inserted into the receptacle  206 , the friction between the port  250  and the device  200  maintains the port in the proper position. 
     In other embodiments, the electrical connections can also provide the mechanical connection. For example, a friction fit between the pins  266  and the sockets  272  may provide sufficient force to keep the portions  256  and  258  connected. A user, however, can remove the portion  256  and replace it. 
     Certain embodiments relate to in vivo (e.g., continuous monitoring) systems. A continuous monitoring system typically includes a sensor that is worn or placed below the skin, a transmitter that collects glucose information from the sensor, and a receiver that collects the information from the transmitter. The sensor can collect glucose level information continuously, periodically, or at other intervals. Advantageously, a user is relieved from having to repeatedly lance his or her body to collect a blood sample once the sensor is inserted, although the sensor (e.g., an electrochemical sensor that is inserted into a body) can be replaced. U.S. Pat. No. 6,175,752, which is hereby incorporated by reference in its entirety, discloses additional examples of a continuous monitoring system. 
     Embodiments of the invention relate to components of a continuous monitoring system that may be replaceable. In one embodiment, the i between the sensor and the transmitter may become contaminated. The transmitter or sensor control unit, for example, may have an interface with the sensor that has been molded to form a barrier between the transmitter&#39;s contacts and circuitry internal to the transmitter. This allows the transmitter&#39;s contacts to be washed without damaging the transmitter&#39;s circuitry. Alternatively, the contacts may be included in a replaceable port that can be replaced as needed. Similarly, the interface on the sensor may be molded to form a barrier to contamination or be replaceable. 
     In these examples, the strip connectors or ports can be used with continuous monitoring systems. As discussed herein, the sensor control unit or transmitter typically has a port to interface with the sensor. This port can be molded such that the contacts can be cleaned to prolong the MTBF. Alternatively, the port can be replaceable and/or washable. A replaceable port allows the continuous system to adapt to different sensor form factors. 
     Embodiments of the invention further extend to kits. Examples of a kit include a measurement device with one or more strip connectors. In some kits, different strip connectors or ports for different types of strips may be included. This allows the measurement device to be used with different strip form factors. The kits may also include a plurality of test strips. In certain examples, the measurement device may be configured for use with disposable test strips as well as with test strips that are configured for continuous monitoring systems. Thus, the measurement device may include a receiver to receive information from a transmitter that collects glucose information from an inserted sensor. The measurement device may also include a strip connector, such as those disclosed herein, for use with single use test strips. 
     The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.