Precision depth control lancing tip

Abstract

A bodily fluid sampling device is operable to lance with a precise depth and express fluid from both fingertip and alternate sites. In one form, the device is operable to adjust the penetration depth of the lancet into the skin. The bodily fluid sampling device includes a lancet adapted to form an incision in skin. A skin contacting member has an orifice through which the lancet extends when lancing the skin. The orifice has a first opening size that is sized to flatten the skin around the lancet during lancing. The orifice has a second opening size that is larger than the first opening size after the incision is formed to express fluid from the incision.

What is claimed is:  
     
         1 . A bodily fluid sampling device, comprising: 
 an incision forming member adapted to form an incision in skin;    an expression member defining an expression opening configured to express fluid from the incision;    a reference member defining an aperture through which the incision forming member extends when forming the incision, the reference member having a reference surface received in the expression opening during formation of the incision to contact the skin and limit penetration depth of the incision forming member into the skin; and    a retraction mechanism coupled to the reference member to retract the reference surface from the expression opening.    
     
     
         2 . The device of  claim 1 , wherein said retraction mechanism includes a spring coupled between the expression member and the reference member to bias the reference surface out of the expression opening after the incision is formed.  
     
     
         3 . The device of  claim 1 , wherein said retraction mechanism includes: 
 a housing connected to the expression member;    a sleeve slidably received around the housing; and    a cam arm pivotally coupled to the housing, the cam arm engaging the sleeve and the reference member to retract the reference surface of the reference member from the expression opening when the sleeve slides towards the skin.    
     
     
         4 . The device of  claim 3 , wherein the retraction mechanism includes a second cam arm pivotally coupled to the housing, the second cam arm engaging the sleeve and the reference member to retract the reference surface of the reference member from the expression opening when the sleeve slides towards the skin.  
     
     
         5 . The device of  claim 3 , further comprising a spring positioned between the housing and the sleeve to bias the reference surface into the expression opening.  
     
     
         6 . The device of  claim 5 , further comprising a nut coupled to the sleeve and engaging the spring.  
     
     
         7 . The device of  claim 3 , further comprising a lock mechanism to lock the reference member in a retracted position in which the reference surface is retracted from the expression opening.  
     
     
         8 . The device of  claim 7 , wherein the lock mechanism includes: 
 a latch coupled to the sleeve; and    a lock tab extending from the cam arm that is engageable with the latch.    
     
     
         9 . The device of  claim 1 , further comprising a lock mechanism to lock the reference member in a retracted position in which the reference surface is retracted from the expression opening.  
     
     
         10 . The device of  claim 1 , wherein the reference member is coupled to the incision forming member to adjust the penetration depth of the incision forming member.  
     
     
         11 . The device of  claim 10 , wherein: 
 the incision forming member has threads; and    the reference member has threads engageable with the threads of the incision forming member for adjusting the penetration depth of the incision forming member.    
     
     
         12 . The device of  claim 1 , further comprising a penetration depth adjustment mechanism to adjust the penetration depth of the incision forming member.  
     
     
         13 . The device of  claim 12 , wherein the penetration depth adjustment mechanism includes an adjuster having a stop surface engageable with the incision forming member to limit the penetration depth of the incision forming member, the adjuster threadedly engaging the reference member for adjusting a distance between the reference surface and the stop surface of the adjuster.  
     
     
         14 . The device of  claim 12 , wherein the penetration depth adjustment mechanism includes the reference member threadedly engaged with the incision forming member for adjusting the penetration depth of the incision forming member.  
     
     
         15 . A bodily fluid sampling device, comprising: 
 a skin lancing member adapted to form an incision in skin; and    a skin contacting member having an orifice through which the skin lancing member extends to form the incision, the orifice having a first opening size that is sized to flatten the skin around the skin lancing member while the skin lancing member forms the incision and a second opening size that is larger than the first opening size after the incision is formed to express fluid from the incision.    
     
     
         16 . The device of  claim 15 , wherein the skin contacting member includes: 
 a reference member defining an aperture having the first opening size; and    an expression member defining an expression opening having the second opening size.    
     
     
         17 . The device of  claim 16 , wherein: 
 at least a portion of the reference member is positioned in the expression opening during formation of the incision; and    the skin contacting member includes a retraction mechanism to retract the reference member from the expression opening after the incision is formed.    
     
     
         18 . The device of  claim 17 , wherein said retraction mechanism includes a spring coupled between the expression member and the reference member to bias the reference surface out of the expression opening after the incision is formed.  
     
     
         19 . The device of  claim 17 , wherein said retraction mechanism includes: 
 a housing connected to the expression member;    a sleeve slidably received around the housing; and    a cam arm pivotally coupled to the housing, the cam arm engaging the sleeve and the reference member to retract the reference surface of the reference member from the expression opening when the sleeve slid towards the skin.    
     
     
         20 . The device of  claim 19 , wherein the retraction mechanism includes a second cam arm pivotally coupled to the housing, the second cam arm engaging the sleeve and the reference member.  
     
     
         21 . The device of  claim 19 , further comprising a spring positioned between the housing and the sleeve to bias the reference surface into the expression opening.  
     
     
         22 . The device of  claim 15 , wherein the skin contacting member includes: 
 a cover defining an aperture having the first opening size; and    a plurality of living hinges extending around the aperture to support the cover, the living hinges being bendable to form an expression opening having the second opening size.    
     
     
         23 . The device of  claim 22 , further comprising an opening size adjustment mechanism.  
     
     
         24 . The device of  claim 22 , wherein: 
 the opening size adjustment mechanism includes 
 an outer tube defining a guide slot, and  
 an inner tube received in the outer tube, the inner tube having a guide member received in the guide slot;  
   said living hinges are connected between the inner tube and the outer tube; and    said guide slot is configured to retract a portion of the inner tube inside the outer tube to bend the living hinges and form the expression opening having the second opening size.    
     
     
         25 . A bodily fluid sampling device, comprising: 
 an incision forming member operable to form an incision in skin;    a reference member having a reference surface positioned proximal the incision forming member to engage the skin around the incision forming member during formation of the incision; and    means for adjusting penetration depth of the incision forming member into the skin.    
     
     
         26 . The device of  claim 25 , wherein the means for adjusting the penetration depth includes an adjuster having a stop surface engageable with the incision forming member to limit the penetration depth of the incision forming member, the adjuster threadedly engaging the reference member for adjusting a distance between the reference surface and the stop surface of the adjuster.  
     
     
         27 . The device of  claim 25 , wherein the means for adjusting the penetration depth includes the reference member threadedly engaging with the incision forming member.  
     
     
         28 . The device of  claim 25 , further comprising: 
 a head portion attached to the incision forming member;    a leaf spring attached to the head;    wherein the reference member includes a cover attached to the leaf spring; and    wherein the means for adjusting the penetration depth includes wheel having a series of steps with different thicknesses positioned between the head and the cover.    
     
     
         29 . The device of  claim 25 , wherein: 
 the reference member includes a living hinge connected to the incision forming member and a stop flange;    the means for adjusting the penetration depth includes 
 a holder holding the incision forming member,  
 a depth control member threadedly engaged with the holder and positioned to contact the stop flange to limit the penetration depth.  
   
     
     
         30 . A method, comprising: 
 forming an incision in the skin with a lancing member of a sampling device through an aperture in the device that has a first opening size;    configuring the aperture to a second opening size that is larger than the first opening size; and    expressing fluid from the incision with the aperture at the second opening size.    
     
     
         31 . The method of  claim 30 , wherein: 
 the device includes a reference member that defines a lancing opening at the first opening size received inside an expression opening at the second opening size defined in an expression member; and    said configuring includes retracting the reference member from the expression opening.    
     
     
         32 . The method of  claim 30 , wherein: 
 the device includes a cover that define a lancing opening with the first opening size and a plurality of living hinges extending around the lancing opening to support the cover;    said configuring includes deforming the living hinges to create an expression opening having the second opening size.    
     
     
         33 . A device for sampling a bodily fluid from an incision in a user's skin, comprising: 
 an expression member including a first, skin-contacting surface defining a first opening;    a depth-control member including a second, skin-contacting surface defining a second opening smaller than the first opening, said depth-control member being movable between first and second positions relative to said expression member, said depth-control member in the first position being retracted relative to said expression member to be displaced from skin received in the first opening of said expression member, said depth-control member in the second position being positioned relative to said expression member to contact skin received in the first opening of said expression member; and    an incision forming member extendable through the second opening of said depth-control member in the second, skin-contacting position.    
     
     
         34 . The device of  claim 33  in which said expression member and said depth-control member comprise concentric, annular-shaped skin-contacting surfaces.  
     
     
         35 . The device of  claim 33  and which further includes means for adjusting the position of the incision forming member relative to said depth-control member to control the depth of penetration of the incision forming member into the user's skin.  
     
     
         36 . The device of  claim 35  in which said incision forming member is connected with and movable relative to said depth-control member.  
     
     
         37 . The device of  claim 36  in which said incision forming member includes a lancet extending beyond the skin-contacting surface of said depth-control member.  
     
     
         38 . A device for sampling a bodily fluid from an incision in a user's skin, comprising: 
 a skin-contacting member including an end portion configurable between two positions, said skin-contacting member in the first position defining a first skin-contacting surface including a depth-control opening, said skin-contacting member in the second position defining a second skin-contacting surface including an expression opening larger than the depth-control opening; and    an incision forming member extendable through the depth-control opening of said skin-contacting member.    
     
     
         39 . A method for sampling a bodily fluid from an incision in a user's skin, comprising: 
 providing a sampling device including an expression member including a first, skin-contacting surface defining a first opening, a depth-control member including a second, skin-contacting surface defining a second opening smaller than the first opening, the depth-control member being movable between first and second positions relative to the expression member, the depth-control member in the first position being retracted relative to the expression member to be displaced from skin received in the first opening of the expression member, the depth-control member in the second position being positioned relative to the expression member to contact skin received in the first opening of the expression member, and an incision forming member extendable through the second opening of the depth-control member in the second, skin-contacting position    placing the sampling device against the user's skin to engage the skin against the skin-contacting surface of the expression member;    positioning the depth-control member in the second position to engage the user's skin;    advancing the incision forming member relative to the expression member to incise the skin to produce a bodily fluid from the incision; and    withdrawing the depth-control member to the first position displaced from the user's skin.    
     
     
         40 . The method of  claim 39  in which the incision forming member is connected with the depth-control member and said positioning of the depth-control member to engage the skin and said advancing the incision forming member to incise the skin are performed simultaneously.  
     
     
         41 . The method of  claim 39  and which further includes, after said advancing, withdrawing the incision forming member from the skin.  
     
     
         42 . The method of  claim 41  in which the incision forming member is connected with the depth-control member and said withdrawing of the depth-control member and said withdrawing of the incision forming member are performed simultaneously.  
     
     
         43 . The method of  claim 39  and which further includes sampling the bodily fluid while maintaining engagement between the skin-contacting surface of the expression member and the skin.  
     
     
         44 . A method for sampling a bodily fluid from an incision in a user's skin, comprising: 
 providing a sampling device comprising a skin-contacting member including an end portion configurable between two positions, the skin-contacting member in the first position defining a first skin-contacting surface including a depth-control opening, the skin-contacting member in the second position defining a second skin-contacting surface including an expression opening larger than the depth-control opening, and an incision forming member extendable through the depth-control opening of the skin-contacting member    placing the sampling device against the user's skin with the skin-contacting member in the first, depth-control position to engage the skin against the skin-contacting surface and received within the depth-control opening;    advancing the incision forming member through the depth-control opening to incise the skin;    withdrawing the incision forming member from the depth-control opening to be displaced from the user's skin; and    reconfiguring the end portion of the skin-contacting member to the second position while maintaining contact between the skin-contacting member and the skin to receive the skin within the expression opening.    
     
     
         45 . The method of  claim 44  and which further includes sampling the bodily fluid while maintaining engagement between the skin-contacting surface of the expression member and the skin.