1. Field of the Invention
The present invention relates, in general, to medical devices and, in particular, to lancing devices.
2. Description of the Related Art
Conventional lancing devices generally have a rigid housing, various operating mechanisms and a lancet that can be armed and launched so as to briefly protrude from one end of the lancing device. For example, conventional lancing devices can include a lancet that is mounted within a rigid housing such that the lancet is movable relative to the rigid housing along a longitudinal axis thereof. Typically, the lancet is spring loaded and launched, upon release of the spring, to penetrate (i.e., “lance”) a target site (e.g., a dermal tissue target site). A bodily fluid sample (e.g., a whole blood sample) can then be expressed from the penetrated target site for collection and analysis. Conventional lancing devices are described in U.S. Pat. No. 5,730,753 to Morita, U.S. Pat. No. 6,045,567 to Taylor et al., U.S. Pat. No. 6,071,250 to Douglas et al., U.S. Pat. No. 6,156,051 to Schraga and U.S. Pat. No. 6,607,543 to Purcell et al., each of which is hereby fully incorporated by reference.
Conventional lancing devices typically require a user to arm the lancing device, urge the lancing device against a target site, and then press a button or other switch to manually activate the lancing device such that a lancet within the device is launched (also referred to as “fired”) towards the target site. The lancet then penetrates (e.g., lances) the target site, thereby creating an opening for the expression of a bodily fluid sample.
The arming and launching of conventional lancing devices involves a multitude of complicated mechanisms that result in the lancing device being relatively large in size, costly to manufacture and cumbersome to operate. In addition, the operation of conventional lancing device mechanisms can induce both vibrations within the lancing device and sounds that increase the level of pain perceived by a user.
Still needed in the field, therefore, is a compact lancing device that is relatively inexpensive to manufacture and easily operated. Also needed is a lancing device that produces a minimal amount of vibration and/or sound during use, thereby decreasing the level of pain perceived by a user.
Compact lancing devices according to embodiments of the present invention are inexpensive to manufacture and can be easily operated (e.g., with one hand of a user). In addition, embodiments of compact lancing devices according to the present invention produce a minimal amount of vibration and/or sound during use, thereby decreasing the level of pain perceived by a user.
A compact lancing device according to an embodiment of the present invention includes a housing, a moveable lancet holder disposed within the housing, a launching mechanism disposed within the housing and arming and trigger mechanisms disposed at least partially within the housing. In addition, the launching mechanism includes a launch spring and a retraction spring.
The lancet holder, launching mechanism, arming mechanism and trigger mechanism are operatively connected to lance a target site with a lancet held by the moveable lancet holder. In addition, the retraction spring is configured in an essentially concentric arrangement with the launch spring.
The concentric arrangement of the retraction spring and launch spring provide compactness to the compact lancing device. In addition, operative connections between the lancet holder and other components of the compact lancing device (e.g., the launching mechanism) are configured to reduce vibration and noise by, for example, limiting rotational movement of the lancet holder during launching.
A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings, of which:
As described in detail below, launching mechanism 112, arming mechanism 108 and trigger mechanism 110 are operatively connected such that a target site (e.g., a user's skin target site) can be lanced with a lancet (e.g., lancet L that includes lancet needle N) held within compact lancing device 100. In this regard, launching mechanism 112 is configured for launching lancet L such that lancet needle N lances a target site, arming mechanism 108 is configured for arming compact lancing device 100 prior to firing the compact lancing device (i.e., prior to launching lancet L), while trigger mechanism 110 is configured to actuate the firing of compact lancing device 100. Furthermore, depth adjustment mechanism 106 is configured for a user to select (i.e., predetermine) needle penetration depth into a target site.
Compact lancing device 100 can be any suitable size but can be beneficially sized to fit within the palm of a user's hand and has, therefore, a typical but non-limiting length in the range of 50 mm to 70 mm and a typical but non-limiting width in the range of about 10 mm to about 20 mm. Such a compact size is beneficial in that it requires less storage space and is less conspicuous than conventionally sized lancing devices.
Housing 102 is generally cylindrical in shape and includes a proximal end 114, a distal end 116, a first surface 118, an arming mechanism orifice 120, a trigger mechanism orifice 122, a window 124, a second surface 126 and a gripping feature 128. Housing 102 can be formed, for example, of rigid materials including, but not limited to, polycarbonate, polyester, polystyrene, polyamide, polyacetal, polyimide, polyketone, polyurethane, polybutyleneteraphthalate and combinations thereof. Housing 102 can also be formed of semi-rigid materials including, for example, polypropylene, high-density polyethylene, polyurethane, ethylene propylene rubber, polymethylpentene and combinations thereof. If desired, housing 102 can be easily manufactured from two elongate pieces that are sonically welded or snap-fit together to create housing 102.
End cap 104 is detachably connected to distal end 116 of housing 102. End cap 104 includes skin engaging surface 130 with opening 132 therein, collar engaging end 134 with raised features 136 and indentations 138.
Depth adjustment mechanism 106 includes a collar 140 and a guide member 142. Collar 140 includes a collar first end 144 with collar rim 146, a collar second end 148, depth setting indicators 150, recesses 152 and internal spiral thread 154. Furthermore, guide member 142 includes an aperture 156, a cam surface 158, a guide member groove 160 (labeled in
Arming mechanism 108 includes a handle 164, a first rim 166, a second rim 168, an internal groove 170 and an internal raised portion 172. Trigger mechanism 110 includes a body 174, a trigger button 176, a spring element 178 and a latch rim 180.
Launching mechanism 112 includes a lancet holder 182, a launch spring 184 (with launch spring first and second ends 186 and 188, respectively) and a retraction spring 190. Lancet holder 182 includes proximal end 192, a distal end 194, a first hollow portion 196, a second hollow portion 198, a first surface 200, a second surface 202, a space 204, an outwardly expandable portion 206, a slit 208, a lip 210, a cam surface 212, a depression 214, an internal surface 216, and a projection 218 (with a projection end 220).
Having introduced various components of compact lancing device 100, details of the interaction and functioning of such components will now be described with reference to
Trigger mechanism 110 is accessible to a user through trigger member orifice 122 on first surface 118 of housing 102 (see, in particular,
As depicted in
In the embodiment of
Lancet holder 182 is generally cylindrical in shape with first hollow portion 196 and second hollow portion 198 disposed at the proximal and distal ends 192 and 194, respectively, of lancet holder 182 (see, for example,
Space 204 of lancet holder 182 is approximately centrally located and bounded by first and second surfaces 200 and 202, respectively. Distal end 194 includes a radially and outwardly expandable portion 206 with a slit 208 configured such that lancet L (e.g., a suitable commercially available lancet) can easily be inserted into and removed from lancet holder 182.
Proximal end 192 includes a lip 210 that engages with first rim 166 of arming mechanism 108 during latching of lancet holder 182. Lip 210 further holds retraction spring 190 in surrounding relationship to proximal end 192 of lancet holder 182. First surface 200 includes a cam surface 212 adjacent to a depression 214 for a spring element 178 of trigger mechanism 110 to cooperate with (e.g., to react against). Second surface 202 includes an elongate projection 218 that, along with cam surface 212 and depression 214, function during arming and triggering operations, as will be described below.
Launch spring 184 is configured to control movement of lancet holder 182. Launch spring first end 186 engages an internal surface of housing's proximal end 114, while launch spring second end 188 engages an internal surface 216 of lancet holder 182 (see
Retraction spring 190 resides substantially within the circumferential space between arming mechanism 108 and lancet holder 182. Retraction spring 190 pulls lancet holder 182 back after lancet needle N has been launched into a target site, dampens vibrations from lancet holder 182 during use of compact lancing device 100 and prevents lancet needle N from penetrating the target site a second time. Retraction spring 190 also returns arming mechanism 108 to a rest position after latching. One end of retraction spring 190 is also engaged by arming mechanism 108 during arming of compact lancing device 100, as will be described below. Retraction spring 190 can be formed from any suitable material including plastic materials (such as polypropylene and polyester), metal materials or any combinations thereof.
Arming mechanism 108 is generally hollow and elongate and is disposed in surrounding relation to lancet holder 182. Internal raised portion 172 of arming mechanism 108 engages one end of retraction spring 190 during arming of compact lancing device 100, as will be described below.
Projection 218 of lancet holder 182 is adapted to slidably move within internal groove 170 (see
Trigger mechanism 110 is generally internally elongate, ring-shaped and disposed in a surrounding relationship to lancet holder 182. Trigger mechanism 110 can move laterally but not longitudinally relative to housing 102.
Spring element 178 projects into body 174 of trigger mechanism 110. Spring element 178 engages cam surface 212 when compact lancing device 100 is armed (see
When compact lancing device 100 is armed, latch rim 180 of trigger mechanism 110 engages projection end 220 of projection 218 and trigger button 176 moves laterally to a triggering position, as depicted in
Depth adjustment mechanism 106 enables a user to predetermine a depth of needle penetration into a target site. End cap 104 includes opening 132 for lancet needle N to pass through and a plurality of indentations 138 such that a user can grip end cap 104 and rotate, tip or pull the end cap away from housing 102 when replacing lancets. End cap 104 can be formed of any suitable material including, but not limited to, elastomeric materials such as rubber, latex or silicone such that when end cap 104 is removed, end cap 104 can optionally deform inward and grab onto lancet L, thereby allowing lancet L to be removed along with end cap 104.
Collar engaging end 134 of end cap 104 is configured to mate with collar first end 144. Collar engaging end 134 includes a plurality of raised features 136 for engaging with a plurality of corresponding recesses 152 of collar 140. Raised features 136 and recesses 152 provide for detent-based retention of end cap 104, yet facilitate easy removal of end cap 104 by, for example, i.e., tipping to one side or pulling off.
Collar 140 includes an internal spiral thread 154 that engages a corresponding cam surface 158 (which is essentially an external spiral thread cam surface) on guide member 142, a collar rim 146 on collar first end 144 and a collar second end 148. Collar 140 is sidably moveable relative to housing 102 and guide member 142 and has a generally hollow cylindrical shape.
Guide member 142 includes an aperture 156 through which trigger mechanism 110 is inserted such that trigger mechanism 110 is nested therein. Guide member 142 further includes a guide member groove 160 (see
Guide member 142 is held stationary relative to lancet holder 182 by attaching guide member 142 to the inner surface of housing 102 via outer protrusions 162 that mate with recesses (not shown) on the inner surface of housing 102. However, any attachment means known to those skilled in the art can be used to secure guide member 142 to housing 102 including, but not limited to a pin, a screw and ultrasonic welding.
Rotation of end cap 104 adjusts the depth of needle penetration. When end cap 104 is rotated, raised features 136 engage with collar's recesses 152 via a spline interface methodology. This causes internal spiral threads 154 of collar 140 to engage cam surface 158 of guide member 142, thereby moving end cap 104 away from or toward housing 102 and changing the distance needle N penetrates into a target site. In this regard,
Arming mechanism 108, trigger mechanism 110, lancet holder 182, collar 140 and guide member 142 can, for example, be formed of rigid materials including, but not limited to, polycarbonate, polyester, polystyrene, polyamide, polyacetal, polyimide, polyketone, polyurethane polybutyleneteraphthalate or combinations thereof. Arming mechanism 108, trigger mechanism 110, lancet holder 182, collar 140 and guide member 142 can optionally contain lubricating additives including, for example, Teflon or graphite to reduce friction (and resulting vibration) therebetween.
All mechanisms of compact lancing device 100 cooperate with a close fit, thereby minimizing vibration during firing of lancet L. In addition, the interface between lip 210 of lancet holder 182 and first rim 166 of arming mechanism 108 can include materials that dampen sound and vibration (e.g., rubber or elastomeric materials). Such a sound/vibration dampening material interface can be formed, for example, as an additional component (e.g., a layer of sound/vibration dampening material) disposed between lip 210 and first rim 166 or by forming lip 210 and/or first rim 166 either partially or completely of a sound and/or vibration dampening material. Use of tight tolerances (such as tight tolerances in the range of 0.0005 inches to 0.003 inches) and sound/vibration dampening materials can reduce the perception of pain by the device user.
Referring to
Compact lancing device 100 is armed by moving arming mechanism 108 toward proximal end 114 of housing 102 such that one end of retraction spring 190 is engaged by internal raised portion 172 of arming mechanism 108 and the other end of retraction spring 190 with lip 210 of lancet holder 182 (see
When arming mechanism 108 is released, both arming mechanism 108 and the end of retraction spring 190 in contact with first rim 166 move back to their original positions (see
Next, skin engaging surface 130 of end cap 104 is contacted with a target site. Subsequently, the skin engaging surface is urged towards the target site, thereby creating a bulge B in the target site (see
When trigger mechanism 110 is triggered (e.g., trigger button 176 is pressed in a lateral direction relative to housing 102), latch rim 180 is disengaged from projection end 220 of lancet holder 182, thereby allowing projection 218 to slide over latch rim 180 and lancet holder 182 to move toward end cap 104 (see
As described above, trigger mechanism 110 has a role in both the arming and triggering of compact lancing device 100, thereby eliminating the need and expense of separate components to perform these functions.
Storage compartment 304 is configured to receive and removably retain items (not shown) related to the use of lancing device 302. Items related to lancing device 302 that can be removably retained in storage compartment 304 include, but are not limited to, lancets, test strips, pharmaceuticals and alcohol swabs. Storage compartment 304 is optionally configured to receive and removably retain items (not shown) unrelated to the use of lancing device 302. Items unrelated to lancing device 302 that can be removably retained in storage compartment 304 include, but are not limited to, coins, pills and medications.
For illustrative purposes only in
Storage compartment 304 is generally elongate and cylindrical in shape and includes a proximal end 310, a distal end 312, a body 314 and a cavity 316 (see
Distal end 312 of storage compartment 304 includes a cap 318 and an opening 320 (see
It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that structures within the scope of these claims and their equivalents be covered thereby.