Abstract:
An analyte and detecting apparatus has a housing and a disposable positionable in the housing. A penetrating member driver is positioned in the housing. A plurality of penetrating members are positioned in the disposable. Each a penetrating member is configured to be coupled to the penetrating member driver. A plurality of sampling chambers are provided with each one including an analyte sensor. A cam disk indexing and drive mechanism is included.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Ser. No. 61/148,767, which application is fully incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to analyte measurement devices, and more specifically, to systems and methods that securely hold a cam disk without the use of more complex non-back drivable gears. 
         [0004]    2. Description of the Related Art 
         [0005]    Lancing devices are known in the medical health-care products industry for piercing the skin to produce blood for analysis. Typically, a drop of blood for this type of analysis is obtained by making a small incision in the fingertip, creating a small wound, which generates a small blood droplet on the surface of the skin. 
         [0006]    Early methods of lancing included piercing or slicing the skin with a needle or razor. Current methods utilize lancing devices that contain a multitude of spring, cam and mass actuators to drive the lancet. These include cantilever springs, diaphragms, coil springs, as well as gravity plumbs used to drive the lancet. The device may be held against the skin and mechanically triggered to ballistically launch the lancet. Unfortunately, the pain associated with each lancing event using known technology discourages patients from testing. In addition to vibratory stimulation of the skin as the driver impacts the end of a launcher stop, known spring based devices have the possibility of firing lancets that harmonically oscillate against the patient tissue, causing multiple strikes due to recoil. This recoil and multiple strikes of the lancet is one major impediment to patient compliance with a structured glucose monitoring regime. 
         [0007]    Success rate generally encompasses the probability of producing a blood sample with one lancing action, which is sufficient in volume to perform the desired analytical test. The blood may appear spontaneously at the surface of the skin, or may be “milked” from the wound. Milking generally involves pressing the side of the digit, or in proximity of the wound to express the blood to the surface. In traditional methods, the blood droplet produced by the lancing action must reach the surface of the skin to be viable for testing. 
         [0008]    When using existing methods, blood often flows from the cut blood vessels but is then trapped below the surface of the skin, forming a hematoma. In other instances, a wound is created, but no blood flows from the wound. In either case, the lancing process cannot be combined with the sample acquisition and testing step. Spontaneous blood droplet generation with current mechanical launching system varies between launcher types but on average it is about 50% of lancet strikes, which would be spontaneous. Otherwise milking is required to yield blood. Mechanical launchers are unlikely to provide the means for integrated sample acquisition and testing if one out of every two strikes does not yield a spontaneous blood sample. 
         [0009]    Many diabetic patients (insulin dependent) are required to self-test for blood glucose levels five to six times daily. The large number of steps required in traditional methods of glucose testing ranging from lancing, to milking of blood, applying blood to the test strip, and getting the measurements from the test strip discourages many diabetic patients from testing their blood glucose levels as often as recommended. Tight control of plasma glucose through frequent testing is therefore mandatory for disease management. The pain associated with each lancing event further discourages patients from testing. Additionally, the wound channel left on the patient by known systems may also be of a size that discourages those who are active with their hands or who are worried about healing of those wound channels from testing their glucose levels. 
         [0010]    Another problem frequently encountered by patients who must use lancing equipment to obtain and analyze blood samples is the amount of manual dexterity and hand-eye coordination required to properly operate the lancing and sample testing equipment due to retinopathies and neuropathies particularly, severe in elderly diabetic patients. For those patients, operating existing lancet and sample testing equipment can be a challenge. Once a blood droplet is created, that droplet must then be guided into a receiving channel of a small test strip or the like. If the sample placement on the strip is unsuccessful, repetition of the entire procedure including re-lancing the skin to obtain a new blood droplet is necessary. 
         [0011]    Early methods of using test strips required a relatively substantial volume of blood to obtain an accurate glucose measurement. This large blood requirement made the monitoring experience a painful one for the user since the user may need to lance deeper than comfortable to obtain sufficient blood generation. Alternatively, if insufficient blood is spontaneously generated, the user may need to “milk” the wound to squeeze enough blood to the skin surface. Neither method is desirable as they take additional user effort and may be painful. The discomfort and inconvenience associated with such lancing events may deter a user from testing their blood glucose levels in a rigorous manner sufficient to control their diabetes. 
         [0012]    A further impediment to patient compliance is the amount of time that at lower volumes, it becomes even more important that blood or other fluid sample be directed to a measurement device without being wasted or spilled along the way. Known devices do not effectively handle the low sample volumes in an efficient manner. Accordingly, improved sensing devices are desired to increase user compliance and reduce the hurdles associated with analyte measurement. 
         [0013]    A further concern is the use of blood glucose monitoring devices in a professional setting. For the professional health care market, single device multiple user is the norm. A sterility barrier between patients is required or a single use professional lancing device is used and then discarded after use. To interface an integrated point of care lancing, sampling and analyte detection device with a multiple user paradigm, each lancet analyte detecting member pair may be isolated from the previous and subsequent user. 
         [0014]    There is a need for an analyte measurement device with an improved disk indexing and drive mechanism. There is a further need for an analyte measurement device that employs a cam drive with a motion profile that is variable in real time to vary force, distance, speed, acceleration, noise levels and isolates cam-follower functions. There is a further need for an analyte measurement device with a cam disk motion profile where all movements are provided by a single motor and control system in order to significantly reduce parts, power and complexity. 
       SUMMARY 
       [0015]    An object of the present invention is to provide an analyte measurement device that has an improved disk indexing and drive mechanism. 
         [0016]    An further object of the present invention is to provide an analyte measurement device that has a cam drive with a motion profile that is variable in real time to vary force, distance, speed, acceleration, noise levels and isolates cam-follower functions. 
         [0017]    Another object of the present invention is to provide an analyte measurement device with a cam disk motion profile where all movements are provided by a single motor and control system in order to significantly reduce parts, power and complexity. 
         [0018]    These and other objects of the present invention are achieved in an analyte and detecting apparatus with a housing and a disposable positionable in the housing. A penetrating member driver is positioned in the housing. A plurality of penetrating members are positioned in the disposable. Each a penetrating member is configured to be coupled to the penetrating member driver. A plurality of sampling chambers are provided with each one including an analyte sensor. A cam disk indexing and drive mechanism is included. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  illustrates one embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism. 
           [0020]      FIG. 2  illustrates another embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism that includes a battery, plate upper, PCB assembly, cam disk, plate lower, bobbin ear and a lancing disk. 
           [0021]      FIG. 3  illustrates an embodiment of an analyte measurement apparatus of the present invention with a cam disk indexing and drive mechanism that has features selected from at least one of, indexing in variable increments, punch follower, indexing in an opposite direction, gripping of the penetrating member as well as un-gripping, park and un-park which is retaining and releasing of the gripper shaft and multiple punching. 
           [0022]      FIG. 4  is a flow chart illustrating in one embodiment of operation of a cam disk indexing and drive mechanism of the present invention. 
           [0023]      FIG. 5  illustrates one embodiment of a ratchet modeling of the present invention with two cams. 
           [0024]      FIG. 6  illustrates one embodiment of a flowchart showing how a cam disk indexing and drive mechanism of the present invention operates. 
           [0025]    As shown in  FIG. 7  illustrates the operation of the indexer. A ratchet pushes a post on the indexer in one direction. An adjustment of indexing can be achieved to a selected active chamber. 
           [0026]      FIG. 8  illustrates one embodiment of the present invention showing timing and angles of a cam disk. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    In one embodiment of the present invention, an improved cam disk indexing and drive mechanism is provided. The present invention is particularly suitable with the analyte measurement and detecting systems disclosed in W.O. 2005/120365, incorporated herein by reference. In one embodiment, the cam disk manages all disposable penetrating member actions with a single motor drive, including but not limited to indexing, punching of one or more seals, and gripping of the penetrating member. 
         [0028]    In one embodiment, a parking lever is provided that can include an over-molded rod, that can be made of a variety of materials including but not limited to carbon and the like. The over-molded rod is securely, safely and reliably constrained during inactivity of a penetrating member by a simple and single rotating cam feature contained within the single cam disk which is held securely without the use of more complex non-back drivable gears. In one embodiment, a pre-described cam disk motion profile is variable in real time to vary force, distance, speed, acceleration, noise levels and isolate cam-follower functions. All movements can be provided by a single motor and control system significantly reducing parts, power, complexity. A low precision low resolution cam disk can be provided that drives a high precision, high resolution penetrating member disposable and provides significant force, reliability, simplicity and accuracy benefits. 
         [0029]    In various embodiments of the present invention, (i) rapid penetrating member cartridge foil detection mapping is achieved with multiple foil detection sensors in parallel or serial use, bi-directional ratcheted indexing movement, (ii) progressive real time foil detection of the in-use chamber ensures a foiled chamber is tested immediately prior to use, increasing safety and reliability, (iii) the cam disk enables seal (foil) detection without additional obligations of punching(s), gripping, or shield insertion which significantly reduces foil and penetrating member loss, (iv) cam disk ratchets and bi-directional drive enable isolate cam-follower functions out of sequence(s) such as independent penetrating member cartridge rotation without progressing sequential or previous cam disk followers, (v) the cam drive significantly simplifies complex and reliable mechanical movements in the handling and preparation of disposable objects, and (vi) an improved hub provides simple positive tactile insertion in any penetrating member cartridge chamber rotational orientation. 
         [0030]    In  FIG. 1 , the cam drive  10  followers are illustrated. It includes the cam drive  10  and the disposable  14  that contains the penetrating members and glucose sensors. A gear box  16  and motor  18  are provided, which are the drive train for the cam disk  20 . The cam includes a plurality of followers. The present invention provides a great deal of precision. Because there is a gear box, the driving system does not require accuracy. Repeatability is achieved because of the cam disk which has multiple operations and features on it. This activates a plurality of functions in the device. This provides a great economy of scale. Everything can be amplified to the disposable without much power. Large forces and speeds can be attained. Very rapid detection of the seals (foils) can be obtained with the present invention. 
         [0031]    In this embodiment, the indexing and drive mechanism includes an actuator  21 , disk cam module  22 , lower/upper plate  24 , parking lever  26 , disk cam  28 , punching lever  30 , slide cam  32 , outset mold  34 , bobbin gear  36 , indexing gear  38  and a center guide  50 . 
         [0032]    Additional elements of the  FIG. 1  embodiment are illustrated in  FIG. 2 . As shown in  FIG. 2 , the indexing and drive mechanism includes a battery  42 , plate upper  44 , PCB assembly  46 , cam disk  48 , plate lower  50 , bobbin ear  52  and a lancing disk  54 .  FIG. 2  shows a rigid chassis for the elements of the cam drive. A rigid structure is created by two plates and four posts. 
         [0033]      FIG. 3  illustrates a cam drive with different features including but not limited to, indexing in variable increments, punch follower, indexing in an opposite direction, gripping of the penetrating member as well as un-gripping, park and un-park which is retaining and releasing of the gripper shaft, multiple punching, and the like. 
         [0034]      FIG. 4  is a flow chart illustrating how the cam disk operates. By way of illustrating, indexing can proceed in two directions, and nested loops can be achieved. This programs a great number of sub-routines that can be performed. 
         [0035]      FIG. 5  shows one embodiment of ratchet modeling of the present invention with two cams  56  and  58  that can be used with the present invention, index cam-1 and an index cam-2. These are then coupled to followers. The followers provide for indexing, punching, parking and gripping. All of these functions can occur at the same time. Additionally, with the present invention, a very repeatable process can be achieved. 
         [0036]    In  FIG. 6 , illustrates a flowchart of how the cam disk can be operated. In this embodiment, the user starts with a test. The disposable seal is then taken into consideration. Indexing occurs at the punching station and then it is moved over to a gripping position. Right before the penetrating member is launched, it is parked. It is also parked after launch. 
         [0037]    As shown in  FIG. 7  the operation of the indexer is illustrated. A ratchet pushes a post on the indexer in one direction. An adjustment of indexing can be achieved to a selected active chamber. 
         [0038]      FIG. 8  illustrates timing and angles of the cam disk. The cam disk can be moved in both x-y, and y-z directions. This provides for movement in three orthogonal directions. In  FIG. 8 , the first column lists follower functions, the second column lists motions, the third column lists the angle that the motion occurs in, the fourth column lists the number of gear teeth and the fifth column lists the time required. 
         [0039]    Expected variations or differences in the results are contemplated in accordance with the objects and practices of the present invention. It is intended, therefore, that the invention be defined by the scope of the claims which follow and that such claims be interpreted as broadly as is reasonable.