Latch mechanism for preventing lancet oscillation in a lancing device
Inventors
PUSEY, Lauren R. • Lamps, Greg
Assignees
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Publication Number
US-10820849-B2
Publication Date
2020-11-03
Expiration Date
Abstract
A lancing device including a latch that pivots between a non-blocking position allowing a lancet carrier and a lancet to advance and retract through a first forward and reverse lancing stroke and a blocking position preventing further/excess/secondary oscillation of the lancet carrier and lancet. The pivotal latch can pivot about an axis perpendicular (e.g., for an L-shaped latch) or parallel/coaxial (e.g., for a sleeve latch) to the advancement and retraction motion of the lancet carrier and lancet.
Core Innovation
A skin lancing device includes a housing, a lancet having a sharp tip, and a lancet carrier movable through a lancing stroke from a retracted position, through a forward portion, to an advanced position puncturing the skin, and through a return portion. A drive mechanism drives the lancet carrier through the lancing stroke, and a charging mechanism charges the drive mechanism. A latch mechanism permits the lancet carrier to travel through the lancing stroke but prevents excess oscillation of the lancet carrier.
The latch mechanism includes a latch member that is spring-biased to a blocking position and pivots between a blocking position, an intermediate non-blocking position, and a press non-blocking position. Operating the charging mechanism moves a latch-pivoting element into engagement with a charge-pivot face of the latch member to pivot the latch member from the blocking position to the intermediate non-blocking position, and a latch retainer retains the latch member in the intermediate non-blocking position to prevent reverse pivoting.
During the forward portion, the latch retainer is withdrawn from engagement with a ramp and the latch member reverse pivots to the press non-blocking position with a pressed surface of the lancet carrier interfering with a pressing surface of the latch member to prevent reverse pivoting back to the blocking position. During the return portion, the pressed surface of the lancet carrier clears interference with the pressing surface of the latch member and the latch member reverse pivots to the blocking position.
With the latch member in the blocking position, if the lancet carrier is driven along the forward portion of the lancing stroke a second time, a drive-stop surface of the latch member engages and blocks a latch-engaging element of the lancet carrier to prevent excess lancet-carrier oscillation. The device is described in embodiments including an L-shaped latch with ramp portions having a tipping point and a second embodiment using a sleeve/tube latch that sequences through charged and discharged states with a spring-biased latch retainer finger.
Claims Coverage
The partial claim set includes one independent claim that defines the overall lancing device architecture and the latch mechanism sequencing, including a second-stroke drive-stop to prevent excess oscillation. The inventive features center on latch-member pivoting among blocking and non-blocking positions under control of the charging mechanism and the carrier stroke.
Spring-biased latch member that pivots through blocking and non-blocking positions to permit travel while preventing excess oscillation
A latch mechanism permits the lancet carrier to travel through the lancing stroke but prevents excess oscillation, where the latch mechanism includes a latch member that is spring-biased and pivots between a blocking position, an intermediate non-blocking position, and a press non-blocking position.
Charging mechanism engages a charge-pivot face to pivot the latch from blocking to intermediate non-blocking and prevents reverse pivoting
Operating the charging mechanism to charge the drive mechanism moves a latch-pivoting element into engagement with a charge-pivot face of the latch member to pivot the latch member from the blocking position to the intermediate non-blocking position, wherein a latch retainer retains the latch member in the intermediate non-blocking position to prevent reverse pivoting.
Forward-stroke interference with a pressing surface to prevent return to blocking during forward travel
As the lancet carrier travels along the forward portion of the lancing stroke, the latch retainer is withdrawn from engagement with a ramp and the latch member reverse pivots to the press non-blocking position with the pressed surface of the lancet carrier interfering with the pressing surface of the latch member to prevent reverse pivoting to the blocking position.
Return-stroke clearing to return the latch member to the blocking position
As the lancet carrier travels along the return portion of the lancing stroke, the pressed surface of the lancet carrier clears interference with the pressing surface of the latch member and the latch member reverse pivots to the blocking position.
Second-forward-stroke drive-stop block to prevent excess lancet-carrier oscillation
With the latch member in the blocking position, if the lancet carrier is driven along the forward portion of the lancing stroke a second time, the drive-stop surface of the latch member engages and blocks the latch-engaging element of the lancet carrier to prevent excess lancet-carrier oscillation.
The inventive structure constrains latch-member pivoting so that the latch member is moved to an intermediate non-blocking position during charging, held during forward travel via interference that prevents return to blocking, returned to blocking during the return portion, and then uses a drive-stop surface to block further forward travel on a second stroke to prevent excess oscillation.
Stated Advantages
Prevents excess oscillation of the lancet carrier.
Blocks a second forward stroke to prevent excess lancet-carrier oscillation.
Documented Applications
Skin lancing using a skin lancing device with a lancet puncturing skin during a lancing stroke.
Interested in licensing this patent?