Cap displacement mechanism for lancing device and multi-lancet cartridge

Abstract

A medical lancing device including a replaceable multi-lancet cartridge. The lancing device includes an advancing mechanism that advances lancets within the cartridge into an active position, separates a protective cap from the active lancet, and energize a drive mechanism of the lancing device. A cap displacement mechanism moves the separated cap out of the travel path of the active lancet. In a first example embodiment, the cap displacement mechanism includes a cantilevered spring arm that displaces the detached cap of the active lancet. In a second example embodiment, the cap displacement mechanism includes a spring-biased cam-driven plunger that displaces the detached cap of the active lancet. Then an activation mechanism releases the energized active lancet to traverse the unobstructed lancing stroke path to pierce the subject's skin at a desired lancing site.

What is claimed is: 
     
         1 . A multi-lancet cartridge assembly for use with and replaceable in a lancing device having an advancer mechanism, a cap-displacement mechanism, and a drive mechanism, the cartridge assembly comprising:
 a disk-shaped cartridge housing;   a disk-shaped carrier rotationally received in the cartridge housing; and   an array of lancets carried by the carrier, each lancet having a lancet body and a lancet tip extending from the body, wherein each of the lancets includes a detachable cap on the tip, wherein the carrier includes a plurality of guide tracks that are transverse to a lancing stroke path and that define an array of transverse guide paths along which the lancet caps are automatically guided and displaced transversely under influence of the cap-displacement mechanism as the lancets are radially retracted before being driven through the lancing stroke path, wherein each one of the guide tracks receives a respective one of the caps, and wherein the guide tracks retain the lancet caps after displacement from the lancets,   wherein the carrier is engageable and moveable by the advancer mechanism to rotate the carrier of lancets within the cartridge housing to sequentially advance the lancets into an active lancet position, and wherein an active one of the lancets in the active position is engageable and movable by the drive mechanism through the lancing stroke from a retracted position to an extended position with the lancet tip extending from the cartridge housing to lance skin.   
     
     
         2 . The cartridge assembly of  claim 1 , wherein the lancet caps define one or more cap guide surfaces that engage and ride along the guide tracks as the caps are displaced from the lancing stroke path. 
     
     
         3 . The cartridge assembly of  claim 2 , wherein the guide tracks engage the cap guide surfaces to retain the active-positioned cap from being retracted with the active-positioned lancet so that the retained active-positioned cap separates from the retracted active-positioned lancet. 
     
     
         4 . The cartridge assembly of  claim 1 , wherein the lancets are radially arranged on the carrier. 
     
     
         5 . The cartridge assembly of  claim 1 , wherein the cartridge housing has a single lancet opening that defines the active lancet position, wherein the tip of the active-position lancet extends through the single lancet opening during its lancing stroke. 
     
     
         6 . The cartridge of  claim 5 , wherein the lancets are radially arranged on the carrier and the cartridge housing has an outer circumferential rim with the single lancet opening defined therein. 
     
     
         7 . The cartridge of  claim 1 , wherein the lancets and the housing have cooperating engagement surfaces that engage each other except when the lancets are in the active lancet position to prevent the lancets from moving radially when not in the active lancet position, and that do not engage each other when the lancets are in the active lancet position to not interfere with the lancets moving radially. 
     
     
         8 . The cartridge assembly of  claim 7 , wherein the cooperating engagement surfaces include a foot on each of the lancets and a circular foot channel defined by the cartridge housing that engages the feet of the lancets. 
     
     
         9 . The cartridge assembly of  claim 8 , wherein the cartridge housing has a radial lancing channel that receives and guides the active-positioned lancet in its lancing stroke, wherein the radial lancing channel defines the active lancet position, and wherein the radial lancing channel extends through the circular foot channel to permit the active-positioned lancet to move radially in its lancing stroke. 
     
     
         10 . The cartridge assembly of  claim 1 , wherein the carrier or the lancets include lancet-count indicia and the cartridge housing has a single viewing opening through which the lancet-count indicia are viewable. 
     
     
         11 . A multi-lancet cartridge assembly for use with and replaceable in a lancing device having an advancer mechanism and a drive mechanism, the cartridge assembly comprising:
 a disk-shaped cartridge housing having a radial lancing channel and an outer circumferential rim with a single lancet opening therein, wherein the radial lancing channel and the single lancet opening are aligned and cooperatively define an active lancet position;   a disk-shaped carrier rotationally received in the cartridge housing, wherein the cartridge housing and the lancet carrier have cooperating mechanical stop surfaces that prevent the carrier from rotating more than one complete revolution to prevent reuse of the lancets, wherein the cooperating mechanical stop surfaces include a groove in the carrier and a pin on the cartridge housing that contact each other after a last one of the lancets is used to prevent further rotation of the carrier; and   a radial array of lancets carried by the carrier, each lancet having a lancet body and a lancet tip extending from the body,   wherein the carrier is engageable and moveable by the advancer mechanism to rotate the carrier of lancets within the cartridge housing to sequentially advance the lancets into the active lancet position, and wherein an active one of the lancets in the active position is engageable and movable by the drive mechanism and guided by the radial lancing channel through a lancing stroke from a retracted position to an extended position with the lancet tip extending through the single lancet opening in the cartridge housing to lance skin.   
     
     
         12 . The cartridge assembly of  claim 11 , wherein the lancets and the housing have cooperating engagement surfaces that prevent the used lancets from moving radially except when in the active lancet position. 
     
     
         13 . The cartridge assembly of  claim 11 , wherein the lancets and the housing have cooperating engagement surfaces that prevent the lancets from moving radially except when in the active lancet position. 
     
     
         14 . The cartridge assembly of  claim 11 , wherein the cartridge housing and the lancet carrier have cooperating mechanical stop surfaces that prevent the carrier from rotating more than one complete revolution to prevent reuse of the lancets. 
     
     
         15 . The cartridge assembly of  claim 11 , wherein the lancets are radially arranged on the carrier. 
     
     
         16 . The cartridge assembly of  claim 11 , wherein the cooperating engagement surfaces include a foot on each of the lancets and a circular foot channel defined by the cartridge housing that engages the feet of the lancets. 
     
     
         17 . The cartridge assembly of  claim 16 , wherein the cartridge housing has a radial lancing channel that receives and guides the active-positioned lancet in its lancing stroke, wherein the radial lancing channel defines the active lancet position, and wherein the radial lancing channel extends through the circular foot channel to permit the active-positioned lancet to move radially in its lancing stroke. 
     
     
         18 . A multi-lancet cartridge assembly for use with and replaceable in a lancing device having an advancer mechanism, a cap-displacement mechanism, and a drive mechanism, the cartridge assembly comprising:
 a disk-shaped cartridge housing having a radial lancing channel and an outer circumferential rim with a single lancet opening therein, wherein the radial lancing channel and the single lancet opening are aligned and cooperatively define an active lancet position;   a disk-shaped carrier rotationally received in the cartridge housing, wherein the cartridge housing and the lancet carrier have cooperating mechanical stop surfaces that prevent the carrier from rotating more than one complete revolution to prevent reuse of the lancets, wherein the cooperating mechanical stop surfaces include a groove in the carrier and a pin on the cartridge housing that contact each other after a last one of the lancets is used to prevent further rotation of the carrier; and   an array of lancets carried by the carrier, each lancet having a lancet body and a lancet tip extending from the body, wherein each of the lancets includes a detachable cap on the tip, wherein the carrier includes a plurality of guide tracks that are transverse to a lancing stroke path and that define an array of transverse guide paths along which the lancet caps are automatically guided and displaced transversely under influence of the cap-displacement mechanism as the lancets are radially retracted before being driven through the lancing stroke path, wherein each one of the guide tracks receives a respective one of the caps, and wherein the guide tracks retain the lancet caps after displacement from the lancets,   wherein the carrier is engageable and moveable by the advancer mechanism to rotate the carrier of lancets within the cartridge housing to sequentially advance the lancets into an active lancet position, and wherein an active one of the lancets in the active position is engageable and movable by the drive mechanism through the lancing stroke from a retracted position to an extended position with the lancet tip extending from the cartridge housing to lance skin.