HK1160371B - Flat lancet immobilization - Google Patents

Description

Flat lancet fixation

Technical Field

The present invention relates generally to the field of lancing, and more particularly to maintaining sterility of a lancet prior to use without impeding movement of the lancet during actuation of the lancet.

Background

Monolithic disposable devices have been proposed in which a lancet is sealed behind a sterile barrier. The difficulty with sealing the lancet behind the sterile barrier is that the sterile barrier is damaged leaving the lancet exposed. For example, if the lancet is not fixed, it may accidentally move and damage and/or puncture the sterile barrier. A compromised sterility barrier may not be able to maintain sterility of the lancet. Cutting a user with a contaminated lancet can cause infection to the user. Furthermore, the test results from contaminated lancets may be inaccurate, which leads to a number of problems, mainly inadequate hygiene for the user.

Other unitary disposable devices have been proposed in which the lancet is sealed within a protective envelope, such as by bonding techniques to form the lancet envelope. In some forms, the lancet enclosure is attached to a test strip to form a biosensor. One bonding technique includes positioning a lancet between a top sheet of material and a bottom sheet of material, and sealing the sheets with an adhesive tape around the lancet to form a lancet enclosure. As another example, a second bonding technique includes sandwiching the lancet between a pair of adhesive coated foils, where the coated foils are heat sealed together to form the lancet enclosure. In either bonding technique, excess adhesive typically adheres the lancet to the foil or layer, which can hinder or impede the movement of the lancet during the cutting process. In other words, the lancet is stuck to one or both layers and is most likely not driven properly into the user's skin to form a sufficient incision in which a body fluid sample can be obtained. In addition, the adhesive tape and/or the adhesive coated foil increase the overall thickness of the lancet enclosure and similarly reduce the number of lancet enclosures that can be stacked in a diagnostic structure. Furthermore, the mechanisms used to apply the adhesive tape between the layers of the envelope and the blade or punch tool used to cut and form the lancet envelope require periodic cleaning to remove excess adhesive from the mechanisms, blade and/or punch tool.

Accordingly, there is a need in the art for improvements.

Disclosure of Invention

In one embodiment, the securement of the lancet within the lancet enclosure is accomplished by tack welding a portion of the top foil into the lancet to form the lancet enclosure. In another embodiment, the fixation of the lancet within the lancet enclosure is accomplished by tack welding together opposing pieces of the cover foil through engagement openings in the lancet. For example, the opposing tabs are pinched or pulled through the engagement opening of the lancet and melted together to form the tack weld.

In a second embodiment, the lancet is secured by a separable connection between the lancet and the pad such that the lancet can be separated from the pad when the lancet is actuated; and the lancet can re-engage the pad after use by moving the lancet back to its initial position with the pad to again secure the lancet. In one form, the lancet defines an receiving end configured to mate with a pad having a positive end. In another form, the lancet includes a male end configured to mate with a pad defining an receiving end.

In another embodiment, the lancet enclosure is attached to a test element to form a flat biosensor. Unimpeded movement of the lancets is advantageous for integrating the lancet enclosure into the test strip to avoid potentially wasting the test strip when movement of the respective lancet is impeded and an inadequate body fluid sample is obtained from the lancet that failed firing. Furthermore, the unimpeded movement of the lancet is also advantageous in diagnostic structures, such as drums, cassettes, or meters, among others, where the lancet may not be readily accessible to a user after being loaded into the diagnostic structure.

Other forms, objects, features, aspects, benefits, advantages, and embodiments of the present invention will become apparent from the detailed description and figures provided herewith.

Drawings

FIG. 1 is a first top exploded view of an integral cutting test strip according to one embodiment.

Fig. 2 is a second top exploded view of the unitary cutting test strip of fig. 1.

Fig. 3 is a third top exploded view of the unitary cutting test strip of fig. 1.

FIG. 4 is a top perspective view of the unitary cutting test strip of FIG. 1 with its lancet in an extended position.

Fig. 5 is a bottom exploded view of the integrated cutting test strip of fig. 1.

Fig. 6 is a top view of a lancet according to another embodiment.

Figure 7 is a top view of a lancet enclosure including the lancet of figure 6 according to one embodiment.

Fig. 8 is a top view of a lancet enclosure according to another embodiment.

Fig. 9 is a perspective view of the sterility sheet in the embodiment of fig. 8.

FIG. 10 is a top view of a locking mechanism according to one embodiment.

Fig. 11 is a top view of a locking mechanism according to a second embodiment.

Fig. 12 is a top view of a locking mechanism according to a third embodiment.

Fig. 13 is a top view of a locking mechanism according to a fourth embodiment.

Fig. 14 is a top view of a locking mechanism according to a fifth embodiment.

Fig. 15 is a top view of a locking mechanism according to a sixth embodiment.

FIG. 16 is a perspective view of the lancet enclosure of FIG. 8 engaged to an engagement blade of the firing mechanism.

FIG. 17 is a perspective view of the integrated disposable device incorporating the lancet enclosure of FIG. 8, loaded into a meter and prior to firing of the lancet.

Detailed Description

For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates.

Any reference in this detailed description to any direction in the drawings, such as up or down or top or bottom, is intended for convenience of description and does not in itself limit the invention or any of its components to any particular positional or spatial orientation.

As mentioned above, one difficulty associated with unitary disposable devices includes sealing the lancet behind a sterile barrier such that movement of the lancet is restricted or limited until the lancet is actuated. If the lancet is movable while sealed behind the sterile barrier, it can inadvertently move and puncture the sterile barrier. The exposed lancet can then become contaminated, which can lead to infection of the user; or the exposed lancet can be damaged, which can cause not only a potential infection but also possible injury to the user. Furthermore, the test results from non-sterile or damaged lancets can be inaccurate, which can lead to a number of problems, the main problem being inadequate hygiene for the user. The securement of the lancet within the lancet enclosure prevents the lancet from puncturing the sterility sheet until the operator is ready to use the lancet. Thus, the sterility of the lancet is maintained, potential injury to the operator or other personnel is prevented, and damage to the lancet is prevented. The inventors have discovered a unique fixation system for limiting lancet movement to maintain sterility of the lancet within the lancet enclosure and to provide unimpeded movement of the lancet when the lancet is actuated. In one form, the lancet is at least partially enclosed by a sterility sheet that keeps the lancet tip sterile to form the lancet enclosure. In one embodiment, movement of the lancet within the lancet enclosure is limited by adhesively or heat tack welding a portion of the sterility sheet to the lancet. In other embodiments, movement of the lancet within the lancet enclosure is limited by thermally tack welding together a pair of opposing cover foils or sterility sheets through an opening in the lancet to limit movement of the lancet. In yet another embodiment, movement of the lancet is limited by attaching the lancet to a pad to form a locking mechanism. For example, the locking mechanism is configured to release the lancet from the pad and reattach the lancet to the pad after the cutting event. In other embodiments, movement of the lancet is limited by a combination of a locking mechanism and heat tack welding of the sterility sheet to the lancet. In some embodiments, the lancet enclosure and/or lancet and pad are attached to the test strip to form an integral disposable device.

Referring initially to fig. 1, 2, 3, 4 and 5, an integral cutting test strip or integral disposable device 20 in accordance with one embodiment will be described. Referring to fig. 1, the unitary cutting test strip 20 includes a lancet assembly or incision forming member 22 for forming an incision in tissue; a sterility sheet or foil 24 for maintaining sterility of the lancet 22; and a test strip or biosensor 26 for obtaining body fluid from the incision. In the illustrated embodiment, both the lancet 22 and the test strip 26 are generally flat such that the unitary cut test strip 20 has a generally flat appearance. Being flat, the plurality of unitary cut test strips 20 can be incorporated into film cassettes, magazine cassettes, drums, and the like, which allows the plurality of unitary cut test strips 20 to be used without the need to separately load and/or handle the used unitary device 20. For example, the generally flat shape allows a plurality of the unitary cut test strips 20 to be stacked on top of each other in a film cassette or wound around a spool in a cartridge. Further, this generally flat shape allows the monolithic cut test strip 20 to be manufactured by a continuous process, wherein layers of component materials may be layered to form a continuous strip of the monolithic cut test strip 20, which may be cut to form individual units or remain attached for use in dark boxes and the like. However, it should be appreciated that the unitary cutting test strip 20 may have a different overall shape in other embodiments.

As can be seen in fig. 1 and 5, the lancet assembly 22 has a retaining element or guide member 28 that at least partially helps to guide the piercing member or lancet 30 during cutting. The lancet 30 is slidingly retained within a guide slot or opening 31 defined in the holder 28. During the cutting process, the guide slot 31 guides the movement of the lancet 30 during both extension and retraction of the lancet 30. In the illustrated embodiment, the lancet 30 and the holder 28 are separate components that are not directly attached to each other. In other embodiments, the lancet is detachably attached to a holder or pad, as will be described in more detail below. For example, the body portion of the lancet defines a receiving or female end configured to mate with a retainer or pad having a pin or male end for holding or locking the lancet and pad together. In another example, which will be described below, the body portion of the lancet includes a pin or male end configured to mate with a retainer defining a receiving end or female end to hold the lancet and pad together. In yet another embodiment described below, the body portion of the lancet includes a pair of protruding sides, and the pad includes a pair of legs, each leg defining a groove sized to receive one of the protruding sides to hold the lancet and pad together.

In the illustrated embodiment, the end stop 32 of the retainer 28 extends inwardly at the slot opening 34 of the guide slot 31 to limit the movement of the lancet 30 to retain the lancet 30 in the guide slot 31. In another embodiment, the retainer has a different shape and does not include an end stop. The lancet 30 has a body portion 35 with one or more stop edges 36 that are wider than the slot opening 34. When the lancet 30 is fully extended, the stop edge 36 of the lancet 30 can contact the end stop 32, thus limiting the travel of the lancet 30. In other embodiments, however, the firing mechanism used to fire the lancet 30 limits the travel of the lancet 30. The neck portion 37 of the lancet 30 extends from the body portion 35 of the lancet 30, which is slightly smaller than the size of the slot opening 34. When the lancet 30 is extended, the neck 37 is received between the end stops 32 so that the end stops 32 can limit the undesired rotation of the lancet 30 when piercing tissue. It should be noted that the sterility sheet 24 helps to constrain the rotation of the lancet out of the plane. In one form, the lancet 30 is 1mil thinner than the holder 28 to minimize friction during actuation, although in other embodiments the dimensions can vary. The lancet 30 has a blade portion or tip 38 extending from a neck 37 that is configured to cut tissue. In the illustrated embodiment, the lancet 30 defines an engagement notch or opening 39 for coupling the lancet 30 to the firing mechanism. In one form, the lancet assembly 22 is at least partially made of medical grade stainless steel, but it should be appreciated that the lancet assembly 22 can be made of other materials, such as ceramic and/or plastic. Further, it is contemplated that the guide member 28 and the lancet 30 can be made of different materials and/or separately. In one embodiment, the guide member 28 and lancet 30 are formed by a photolithographic technique in which a metal sheet is lithographically printed to form both the guide member 28 and lancet 30, and in other embodiments, the lancet assembly 22 is made via stamping. In other embodiments, the holder 28 is stamped and formed from a plastic sheet via a rotary die, and the lancet 30 is made from metal. In still other embodiments, the lancet assembly 22 can be made by other techniques.

Referring to fig. 1 and 2, after the lancet assembly 22 is formed, the lancet assembly 22 can then be packaged into a sterility sheet 24. As will be appreciated from the discussion below, the lancet assembly 22 can be packaged into the sterility sheet 24 before, during, or after it is sterilized. In the illustrated embodiment, the sterility sheet 24 is a metal foil sheet, and in other embodiments, the sterility sheet 24 is made of plastic. In one particular form, the sterility sheet 24 is a 19-30 micron thick polyethylene terephthalate (PET) foil. It should be appreciated that the sterility sheet 24 can be made of other types of materials and can have different dimensions. In manufacture, the sterility sheet 24 is folded into two flaps 40 with a crease or fold 42 therebetween, as shown in fig. 1. After folding, the lancet assembly 22 is sandwiched between the two tabs 40 in fig. 2, such that the fold 42 closes the slot opening 34 of the guide slot 31. As shown in fig. 3, the tabs 40 are secured to opposite (flat) sides of the lancet assembly 22 such that the lancet 30 is sealed inside the guide slot 31 with the slot opening 34 closed by the fold 42. In one form, an adhesive is used to secure the sterility sheet to the guide member 28. Adhesive is applied to the guide member 28 around the guide slot 31 but not to the lancet 30 so that the lancet 30 can still slide within the guide slot 31. While an adhesive is used in the illustrated embodiment, it should be understood that the sterility sheet 24 can be sealed to the guide member 28 in other ways (e.g., by heat sealing or laser welding). As will be described in more detail below, one flap 40 or both flaps can be adhered to the lancet 30 by thermally positioning or melting a portion of one flap 40 or both flaps onto the lancet 30 to form a tack weld. The tack weld limits movement of the lancet 30 within the guide slot 31 until the tack weld is broken. As will also be described in more detail below, a portion of each tab 40 is pulled through the engagement notch or opening 39 of the lancet 30 and melts, such that the melted portion of the tab 40 pulls the two tabs 40 together to form a tack weld and limit movement of the lancet 30 within the guide slot 31. Movement of the lancet 30 is limited until the tack weld is broken. For clarity, the figures only show how the individual integral cut test strips 20 are formed, but it is contemplated that in other embodiments, the integral cut test strips 20 are manufactured in a continuous process. In a continuous process, the sterility sheet 24 is a continuous layer unwound from a spool and folded around a continuous layer or tape of the lancet assembly 22, which is similarly wound from the spool. In one variation, the lancet assembly is singulated (singulated) from the spool before being sealed in place.

Once joined together, the lancet assembly 22 and the sterility sheet 24 form a lancet package or envelope 44. As described above, the lancet assembly 22 can be sterilized prior to being enclosed within the sterility sheet 24. The lancet assembly 22 can be sterilized by any number of sterilization techniques as will occur to those of skill in the art, such as by chemical, thermal, and/or radiation sterilization techniques, and the like. It should be understood that all or part of the lancet assembly 22 can be sterilized. For example, the lancet 30 and the guide slot 31 can only be sterilized when desired. In another embodiment, the lancet assembly 22 is sterilized after the lancet assembly 22 is enclosed inside the lancet enclosure 44. In one form, the radiation sterilization technique is used after the lancet 30 is closed by the sterility sheet 24. In the case of the lancet enclosure 44, the sterility of the lancet assembly 22 can be performed without exposing the test strip to the undesirable effects of lancet sterility.

In the illustrated embodiment, the test strip 26 is an electrochemical type test strip. In one particular form, the test strips 26 comprise modified versions of ACCU-CHEK brand test strips (Roche Diagnostics GmbH), although it is contemplated that other types of test strips may be used. For example, in other embodiments, the test strip 26 may comprise an optical type test strip or may otherwise analyze the fluid sample. At one end, the test strip 26 in the illustrated embodiment includes a connection portion 46 having electrical contacts 47, the electrical contacts 47 communicating the sample readings to the meter. Opposite the connecting portion 46, the test strip 26 has a capillary channel 48 with a capillary opening 49 configured to draw a body fluid sample from the incision formed by the lancet 30 via capillary action. As should be appreciated, the test strip 26 inside the capillary channel 48 includes an analysis region that includes electrodes (e.g., working, counter, and reference electrodes); and reagents for analyzing the fluid sample. In one form, the connection portion 46 is connected to a meter and sample readings from electrodes in the analysis region are transmitted to the meter via electrical contacts.

In fig. 3 and 4, the test strip 26 also defines a release slot 51 through which the blade tip of the cam arm extends when the lancet 30 is engaged during loading and firing. In addition, relief groove 51 may be used to vent air from capillary passage 48 as fluid is collected. The length of the release slot 51 is approximately similar to the length of the cutting stroke of the firing mechanism used to actuate the lancet 30. When the lancet enclosure 44 is attached to the test strip 26, the engagement notch 39 on the lancet 30 is aligned with the release slot 51 in the test strip 26. In one embodiment, the blade tip of the cam arm for the firing mechanism extends through the engagement notch 39 of the lancet 30 and into the release slot 51. In so doing, the blade tip pierces the sterility sheet 24. During the cut, the cam arm extends and retracts the lancet 30 relative to the test strip 26 via the blade. When the lancet 30 is extended, the tip 38 of the lancet 30 pierces the sterility sheet 24 at the fold 41, as shown in FIG. 4. In one form, the sterility sheet 24 is weakened at the fold 42 to facilitate piercing by the lancet 30, but in other forms the fold 42 is not weakened. After the lancet 30 is retracted into the guide slot 31, the two tabs 40 of the sterility sheet 24 can frictionally hold the lancet 30 inside. By engaging the lancet 30 in this manner, the risk of accidental puncturing by the integrated lancing test strip 20 is reduced because it is more difficult to manually and/or accidentally actuate the lancet 30. It should be appreciated that the lancet assembly 22 can incorporate other structures for engaging the lancet 30. For example, the engagement notch 39 in the lancet 30 can be replaced by a protrusion or a button. It is also contemplated that the lancet may be fired by non-mechanical and/or non-contact techniques, which do not require piercing the sterility sheet 24. By way of example, the lancet 30 in other embodiments is magnetized and magnetically fired through a voice coil driver. Enclosing the lancet 30 within the sterility sheet 24 both before and after the cut reduces the risk of contamination and also reduces the risk of accidental injury.

A cutting system according to one embodiment will be described with reference to fig. 6 and 7. As shown, fig. 6 illustrates a lancet 180 that shares several features with the lancet 30 described above with reference to fig. 1-5. For example, the lancet 180 has a body portion 35 with a stop edge 36, a neck portion 37, a tip 38, and an engagement opening (notch) or keyhole 142. For ease of illustration, these common features will not be described in detail below, but reference may be made to the foregoing discussion of these common features in U.S. patent application No. 11/551,414 filed on 10/20 2006, which is incorporated herein by reference. The lancet 180 includes an anchor point (tack spot) 182 to identify where a portion 188 of the sterility sheet 24 is adhered or welded to the lancet 180 on the lancet 180, as will be described in more detail below. In the illustrated embodiment, the anchor point 182 is located on the body portion 35. As will be appreciated, the portion 188 of the sterility sheet 24 attached to the lancet 180 at the anchor point 182 secures or locks the lancet 180 prior to use or actuation to avoid damaging the sterility sheet 24. To release the lancet 180 from the sterility sheet 24, a blade or other device pierces the portion 188 of the sterility sheet 24 to break the bond or tack weld between the sterility sheet 24 and the anchor point 182 of the lancet 180. In other embodiments, the lancet 180 is actuated to break the positioning weld between the sterility sheet 24 and the positioning point 182. After breaking the tack weld or bond, movement of the lancet 180 is not impeded by the sterility sheet 24 and the tack weld 188.

As mentioned previously, the anchor point 182 is located on the lancet 180 to identify the attachment location between the sterility sheet 24 and the lancet 180. For example, anchor point 182 may be located on neck portion 37. Further, in other embodiments, one or more anchor points 182 can be located on the lancet 180. As shown, anchor point 182 is circular in shape; however, in other embodiments, anchor point 182 may be a different shape, such as a rectangle, triangle, or oval.

As described above, the anchor point 182 is sized, shaped, and positioned on the lancet 180 such that the portion 188 of the sterility sheet 24 is adhered to the lancet 180 at the location of the anchor point 182. Attaching the portion 188 of the sterility sheet 24 to the lancet 180 secures the lancet 180 within the lancet enclosure 184. One technique for adhering the portion 188 of the sterility sheet 24 to the lancet 180 is to melt the portion 188 onto the lancet 180 at the location of the anchor point 182. Specifically, one way to fuse the sterility sheet 24 to the lancet 180 is with a laser.

The underlying principle of laser welding a sterile sheet to a lancet for the purposes of this embodiment is that for any given type of laser, there is a transmissive (or transparent) material that will not absorb the laser energy (and as a result, pass therethrough) and a black (or absorptive) material that will absorb the energy. As will be described in more detail below, it is important to note that the terms "through" and "black" refer to the laser energy absorption characteristics of a material, not necessarily referring to translucency, opacity or color thereof. In one embodiment, these adjacent transmissive and black materials are chemically and physically substantially the same (e.g., the same or nearly the same polymer substrate, the same or nearly the same melting point). In other embodiments, the adjacent transmissive material and black material are chemically and physically different. In the embodiment depicted in fig. 6 and 7, the laser would be directed at the transparent layer of the sterility sheet 24 at the location of the anchor point 182 of the lancet 180. The laser energy passes through the sterility sheet 24 and is absorbed by the black anchor points 182. The black anchor point 182 becomes hot and then the portion 188 of the sterility sheet 24 corresponding to the anchor point 182 melts. The melted portion 188 then cools, leaving the tack weld 186 that adheres the sterility sheet 24 to the lancet 180. Other laser welding techniques will be discussed below.

Another technique for fusing the portion 188 to the lancet 180 is to employ a hot pin. The hot pin applies heat to the sterility sheet 24 at the location of the anchor point 182 to melt the portion 188 and form an anchor weld 186 between the sterility sheet 24 and the lancet 180.

In one form, the anchor point 182 is formed on the surface of the lancet 180 by chemically etching the surface. In other forms, the anchor point 182 can be formed by other techniques, such as painting a portion of the surface of the lancet 180, printing a dark spot on the surface of the lancet 180, applying an adhesive mark to a portion of the surface of the lancet 180, and/or burning a portion of the surface of the lancet 180. Generally, the size and shape of the locating weld 186 corresponds to the size and shape of the locating point 182. The tack weld 186 can be sized depending on the amount of shear force required to break the bond between the tack weld 186 and the lancet 180 to release the lancet 180 from the sterility sheet 24. For example, the larger size of the tack weld 186 requires more force to release the lancet 180 from the sterility sheet 24 than the force required to break the smaller size tack weld 186.

A cutting system according to another embodiment is described with reference to fig. 8 and 9. Fig. 8 illustrates a lancet 280 that shares several common features with the lancet 30 and lancet 180 described with reference to fig. 1 and 6, respectively. The lancet 280 defines an engagement opening 282 that is similar to the engagement opening 142 of the lancet 180. For the sake of brevity, these common features will not be described in detail below, but reference is made to the foregoing discussion of these common features. As described above, the lancet 280 is placed within the guide member 28. Sterility sheet 24 is folded over lancet 280 and guide member 28 to form lancet enclosure 284.

As shown in fig. 8 and 9, when the lancet 280 is enclosed within the sterility sheet 24, the sterility sheet 24 includes an anchor point 286 located on the engagement opening 282 of the lancet 280. In this form, the anchor points 286 are shaped on each tab 40 of the sterility sheet, as shown in FIG. 9. Anchor point 286 is similar to anchor point 182 described above; however, the anchor points 286 are located on the sterility sheet 24. The anchor points 286 may be any shape or size.

In one form, the anchor points 286 are melted such that the tab 40 is pulled through the engagement opening 282 to crimp the tab 40 through the engagement opening 282. As the molten anchor point 286 of the flap 40 cools, an anchor weld 288 is formed to limit the movement of the lancet 280 within the lancet enclosure 284. As the lancet 280 moves, e.g., during shipment or prior to use of the lancet 280, the positioning weld 288 limits the movement of the lancet 280 within the lancet enclosure 284 so that the lancet 280 does not pierce the sterility sheet 24. To form an incision in the skin, a blade or other piercing mechanism pierces the tack weld 288 to break the bond between the tabs 40 and separate the tabs 40. In another embodiment, the lancet 280 is actuated with sufficient force to break the positioning weld 288 and separate the tabs 40. In either embodiment, after piercing or breaking the positioning weld 288, the tab 40 of the sterility sheet 24 no longer obstructs the movement of the lancet 288.

Specifically, one way to fuse the locating points 286 on the fins 40 is to use a laser. The underlying principle of laser welding two sterile sheets together for purposes of embodiments of the present invention is that, for any given type of laser, there is a transmissive (or transparent) material that will not absorb the laser energy (and, as a result, pass therethrough) and a black (or absorptive) material that will absorb the energy. As noted above, it is important to note that the terms "pass-through" and "black" refer to the laser energy absorbing characteristics of a material, and do not necessarily refer to translucency, opacity, or color thereof. In one embodiment, these adjacent transmissive and black materials are chemically and physically substantially the same (e.g., the same or nearly the same polymer substrate, the same or nearly the same melting point). In the embodiment shown in fig. 8 and 9, the laser beam will be directed at the location point 286 of the sterility sheet 24 over the engagement opening 282 of the lancet 280. A laser beam may be directed at each location point 286 and applied to both location points sequentially or simultaneously. The anchor points 286 absorb the laser energy. The anchor points 286 of the sterility sheet 24 become heated and melt. The melted locating points 286 then cool, leaving locating welds 288 that adhere the tabs 40 of the sterility sheet 24 to each other through the engagement openings 282.

In one embodiment, the melting of fins 40 does not occur through the entire thickness of any of fins 40. That is, the black anchor points 286 are typically only melted therein to a certain depth for a given laser energy.

Another technique for melting the anchor point 286 and pulling the tab 40 through the engagement opening 282 of the lancet 280 is to employ a hot pin. The hot pin applies heat to the sterility sheet 24 at the location of the anchor point 286 to melt the tab 40 and form an anchor weld 288 that pinches the tab 40 and pulls the tab 40 through the engagement opening 282 of the lancet 280.

The locating weld 288 generally corresponds to the shape and size of the locating point 286. In one embodiment, the tack weld 288 does not exceed the overall thickness of the lancet 280. In this embodiment, the additional lancet package 284 can be stacked in a drum or meter since the tack weld 288 does not exceed the overall thickness of the lancet 280.

Another embodiment shown in fig. 10 illustrates a locking mechanism 378 for releasably restricting movement of the lancet 380. Locking mechanism 378 includes a lancet 380 releasably secured by a pad 382. The lancet 380 is similar to the lancet 180 described above. In another form, lancet 380 and pad 382 are coupled with test strip 26. Further, lancet 380 and pad 382 can be enclosed within sterility sheet 24 to form a lancet enclosure, as described above. In this embodiment, lancet 380 is releasably secured by pad 382 to maintain sterility sheet 24 intact prior to actuating lancet 380 and separating lancet 380 from pad 382. The lancet 380 defines a receiving end 384 at a base end 386. Pad 382 includes an insertion portion 388 to connect with receiving end 384 of lancet 380 to hold or lock lancet 380 with pad 382. The receiving end 384 and the insertion portion 388 are similarly sized and complementarily shaped such that the insertion portion 388 and the receiving end 384 mate together. In the illustrated embodiment, the receiving end 384 is formed in a keyway shape and the insertion portion 388 is formed in a corresponding key shape. Receiving end 384 and insertion portion 388 are also configured such that lancet 380 or pad 382 is forced apart when receiving end 384 releases insertion portion 388.

Base end 386 defines a relief notch 390 adjacent deformable portion 392. The deformable portion 392 and the relief groove 390 deform as needed when the insertion portion 388 is inserted into or removed from the receiving end 384. When deformable portion 392 and release groove 390 deform, a user holding lancet 380 will perceive a tactile sensation and/or hear an audible sound, thereby imparting a spring-like property to locking mechanism 378. Furthermore, after lancet 380 is used, insertion portion 388 can be reinserted into receiving end 384 to secure lancet 380 with pad 382. Reattaching the lancets 380 to the lancet enclosure with the pad 382 reduces the likelihood of accidental sticks by used lancets 380. In one embodiment, the receiving end 384 is formed by chemically etching the surface of the lancet 402.

In another embodiment, a locking mechanism 400 is shown in fig. 11 having a lancet 402 releasably secured by a pad 404. The locking mechanism 400 is similar to the locking mechanism 378. Locking mechanism 400 includes a lancet 402 and a pad 404. The lancet 402 is similar to the lancet 180 described above. For the sake of brevity, features of the lancet 402 that are similar to the lancet 180 will not be described again below. Lancet 402 defines a receiving end 406 at a base end 408. Receiver 406 is similar to receiver 384. The liner 404 includes an insert portion 410. The insertion portion 410 is similar to the insertion portion 388. In the illustrated embodiment, the insertion portion 410 is formed in a key shape and the receiving end 406 is formed in a corresponding key slot shape. In other embodiments, the insertion portion 410 and the receiving end 406 are shaped differently but still complementary to each other. The base end 408 includes a deformable portion 411 that is located between the relief slot 412 and the insertion portion 410. However, the receiving end 406 includes a deformable portion 411 located between a pair of release slots 412. As shown, each slot 412 is bent out of shape (flair) from the keyway shape of the receiving end 406. Further, each slot 412 is arcuate or crescent shaped; however, in other embodiments, the slots 412 may be differently shaped. When the insertion portion 410 is inserted into the receiving end 406, the deformable portion 411 and the release slot 412 deform such that the user hears an audible sound and/or perceives a tactile sensation, thereby imparting a spring-like property to the locking mechanism 400. After lancet 402 is used, the movement of lancet 402 relative to pad 404 can be fixed. For example, the insertion portion 410 is inserted into the receiving end 406 to lock the lancet 402 with the pad 404, thereby restricting movement of the lancet 402 and preventing accidental sticks from being made by the used lancet 402. After lancet 402 is reattached to pad 404, the movement of lancet 402 is fixed to avoid accidental movement of lancet 402 away from pad 404.

In fig. 12, a locking mechanism 420 is shown having a lancet 422 releasably secured by a pad 424. The lancet 422 is similar to the lancet 180 described above. For the sake of brevity, features of the lancet 422 that are similar to the lancet 180 will not be described again below. The lancet 422 defines a receiving end 426 at a base end 428. The pad 424 includes an insertion portion 430 for insertion into the receiving end 426 of the lancet 422. Receiving end 426 and insertion portion 420 are similarly sized and complementarily shaped such that insertion portion 430 is inserted into and retained within receiving end 426. In the illustrated embodiment, the receiving end 426 has a key slot shape and the insertion portion 430 has a complementary key shape. In other embodiments, receiving end 426 and insertion portion 430 are shaped differently, but still releasably locked together.

In fig. 13, a locking mechanism 440 is shown that includes a lancet 442 releasably secured by a pad 444. The lancet 442 is similar to the lancet 180 described above. For the sake of brevity, features of the lancet 442 that are similar to the lancet 180 will not be described again below. Lancet 442 includes a body portion 35 having a pair of protruding sides 446 for connection to a pad 444, as described below. Each projection side 446 is curved and projects from the body portion 35. In other embodiments, each projection side 446 may be different from one another or shaped similarly to one another. The body portion 35 of lancet 442 also includes a pair of release slots 448 adjacent the projecting sides 446. As shown, each relief slot 448 has a crescent shape with a curvature similar to that of the protruding side 446. In other embodiments, the relief slots 448 may be shaped differently. In one form, the release slots 448 are formed by chemically etching the lancet 442.

As shown in fig. 13, the pad 444 includes a pair of leg portions 450. Each of the pair of legs 450 defines a groove 452, the grooves 452 having a similar size and complementary shape to the protruding sides 446, such that the protruding sides 446 nest in the grooves 452 to retain the lancet 442 in the pad 444. Release slots 448 are configured and positioned in body portion 35 such that protruding sides 446 and release slots 448 can deform, thereby imparting a spring-like property to lancet 442 and pad 444 as protruding sides 446 of lancet 442 are inserted into and/or retrieved from grooves 452 of pad 444. In one form, the leg 450 is configured to bend as the protruding side 446 of the lancet 442 is inserted into the groove 452 of the pad 444 and/or retrieved from the groove 452. When the protruding side 446 is inserted into the groove 452 and/or retrieved from the groove 452, the user perceives a tactile sensation and/or the user hears an audible sound. As can be appreciated, securing the lancet 442 to the unitary cut test strip with the pad 444 after use of the lancet 442 reduces the risk of potentially injuring and/or contaminating a person with the used lancet 442.

Another embodiment of a locking mechanism 480 is shown in fig. 14 having a lancet 482 releasably secured by a pad 484. Lancet 482 is similar to lancet 442 and liner 484 is similar to liner 444. For the sake of brevity, similar features of the lancet 482 and the pad 484 will not be described again below. The lancet 482 includes a body portion 35 defining a pair of grooves 488 for receiving and releasably retaining the protruding sides 490 of the pad 444, as will be described below. Each groove 488 has a curved shape and forms a depression in the body portion 35. In other embodiments, the groove 488 may be shaped differently.

The liner 484 includes a pair of legs 486, each leg 486 having a protruding side 490. Each protruding side 490 has a curved shape that is similarly sized and complementarily shaped as the recess 488 such that the protruding side 490 nests in the recess 488. The nesting of protruding sides 490 with grooves 488 releasably secures lancet 482 with liner 484. In this embodiment, leg 486 is configured to bend as body portion 35 of lancet 482 is inserted into pad 484 and/or retrieved from pad 484 so that the user perceives a tactile sensation and/or the user hears an audible sound. As will be appreciated, securing the lancet 482 with the pad 484 on the unitary cut test strip after the lancet 482 is used reduces the risk of potentially injuring and/or contaminating a person with the used lancet 482.

Another embodiment of a locking mechanism 500 is shown in fig. 15. In this embodiment, the locking mechanism 500 includes a used lancet 502 connected to a pad 504. In this embodiment, the sterile lancet 502 is releasably secured by the sterility sheet 24 prior to actuation of the unused or sterile lancet 502, as shown in fig. 6, 7, 8, and/or 9 and described above. After the lancet 502 forms an incision in the skin, the lancet 502 is retracted into the guide slot or opening 31 and secured by the pad 504, as described below. The pad 504 is configured to hold the lancet 502 after the lancet 502 has been contaminated to prevent reuse of the lancet 502. Lancet 502 includes a body portion 35 having a pair of insertion legs 506. The body portion 35 of the lancet 502 also defines a pair of slots 508, with each slot 508 positioned adjacent to each leg 506. The pad 504 includes a pair of receiving legs 510. Each receiving leg 510 defines a receiving slot 512 that is sized and shaped to hold one insertion leg 506 to limit movement of the lancet 502 when the lancet 502 is connected to the pad 504. A portion of each leg 506 fits into one of the receiving slots 512 to retain the lancet 502 in the pad 504. In this embodiment, the configuration of the insertion leg 506 and the receiving slot 512 secures the lancet 502 to the pad 504 after the lancet 502 is used to avoid re-use of the contaminated lancet 502.

Fig. 16 and 17 show the blade 146 of the firing mechanism engaging the engagement opening 282 in the lancet 280. Fig. 16 and 17 illustrate the blade 146 of the firing mechanism, and FOR the sake of brevity, these common features will not be described in detail below, but reference is made TO the foregoing discussion of these common features described in U.S. patent application No. 11/551,414 entitled "SYSTEM AND METHOD FOR BREAKING A STERILITY SEAL TO ENGAGE A LANCET", filed on 10/20/2006, which is incorporated herein by reference. The blade 146 in the depicted embodiment is a double edged blade having opposing cutting edges 150 configured to cut a path of travel or crack in the tack weld 288 during firing of the lancet 280. In the illustrated embodiment, blade 146 pierces positioning weld 288 through lancet enclosure 284 to break positioning weld 288. After piercing the tack weld 288, the broken tack weld 288 no longer obstructs the movement of the lancet 280. In another embodiment, the lancet 280 is actuated by a sufficient force to break the tack weld 288. In either embodiment, the broken tack weld 288 no longer obstructs the movement of the lancet 280.

While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the invention as defined by following claims are desired to be protected. All publications, patents and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent or patent application were specifically and individually indicated to be incorporated by reference and were set forth in its entirety herein.

Claims (9)

1. A unitary disposable device comprising:

a test sensor configured to analyze a bodily fluid; and

a lancet enclosure coupled to the test sensor, the lancet enclosure comprising:

a cover foil;

a lancet disposed inside the cover foil, wherein the cover foil covers at least a lancet tip of the lancet; and

the cover foil includes a hot tack weld configured to secure the lancet within the lancet enclosure;

the lancet defines an opening; and

the hot tack weld attaches the opposing pieces of cover foil together through an opening in the lancet.

2. The unitary disposable device of claim 1, wherein the heat tack weld secures the cover foil to the lancet.

3. The unitary disposable device of claim 1, further comprising:

a locking mechanism configured to retain the lancet within the lancet enclosure after the lancet is actuated.

4. The unitary disposable device of claim 3, further comprising:

the thermal tack weld is configured to secure the lancet prior to actuation of the lancet;

the locking mechanism includes a gasket having an insertion portion; and

the lancet defines a keyway, and the insertion portion of the pad has a key shape that attaches the lancet to the pad after the lancet is actuated.

5. A method of forming a unitary disposable device comprising:

covering at least the lancet tip of the lancet with a cover foil to form a lancet enclosure;

melting a portion of the cover foil to form a hot tack weld to secure the lancet;

pressing the opposing pieces of the cover foil together through the engagement opening of the lancet; and

wherein melting the portion of the cover foil comprises melting a pinched portion of the opposing sheets to form the heat tack weld.

6. The method of claim 5, further comprising:

forming an integrated disposable device by coupling the lancet enclosure to a test element configured to analyze a body fluid.

7. The method of claim 5, wherein melting the portion of the cover foil comprises laser welding the portion of the cover foil to the lancet to form the heat tack weld.

8. The method of claim 5, further comprising:

the thermal tack weld is configured to secure the lancet prior to actuation of the lancet; and

forming a locking mechanism on the lancet that secures the lancet after the lancet is actuated.

9. The method of claim 5, further comprising:

sterilizing the lancet; and

attaching the lancet enclosure to a test element to form an integrated disposable device.