SE548014C2

SE548014C2 - Safety lancet

Info

Publication number: SE548014C2
Application number: SE2450339A
Authority: SE
Inventors: Göran Ewerlöf
Original assignee: Wagewe Innovation Ab
Priority date: 2024-03-27
Filing date: 2024-03-27
Publication date: 2026-01-13
Also published as: WO2025202000A1; SE2450339A1

Abstract

The present invention relates to a safety lancet (10) comprising a hinge (32) arranged to the lancet body (12), a carrier (40) comprising a penetration element (42) and connected to the hinge (32) and being linearly movable between inside a lancet body and with the penetration element (42) protruding through the passage (16), a flexible actuator (50) extending in a proximal direction and with an end (52) resting on a flexible force element (48), an activator (26) connected to the actuator (50), wherein a manual movement of the activator (26) causes the free end (52) of the flexible actuator (50) to move along the force element (48) and biases the force element (48) such that the actuator (50) is pushed in the distal direction, building up a force in the actuator (50), until the manual movement of the activator (26) will push the actuator (50) off the force element (48), wherein the force of the actuator, move the penetration element (42) rapidly and perform a penetration.

Description

[0001] The present application relates to a safety lancet for use in connection with collection of blood samples from a finger of a patient.

[0003] BACKGROUND OF INVENTION

[0004] Lancets are widely used when blood samples are to be collected from patients, wherein the tip of a finger is punctured or penetrated by a penetration element and drops of blood are collected. In order to minimize the risk of contamination from blood on the pointed tip of the lancet, so called safety lancets have been developed and have become standard in todays health care.

[0006] The safety lancets are provided with different types of mechanisms that retract the needle into a body of the safety lancet after completed penetration. Thus, the needle is hidden after use, minimizing the risk of accidental needle sticks. The safety lancet is then discarded in a safety box or sharps container. Moreover, the mechanisms of the safety lancet are often designed so that the needle is rapidly pushed into penetration when the safety lancet is activated, which reduces the pain experienced by the patient. Many of the safety lancets on the market are provided with mechanisms comprising metal springs that provide the penetration force.

[0008] One drawback with the use of metal springs is that they alone provide the force on the needle and when choosing the spring force, there is a balance between enough puncturing force for varying skin thicknesses and not excessive force that may cause discomfort to the patient or different penetration depths due to this. Moreover, the use of metal springs increases the manufacturing cost as well as increased recycling costs.

[0010] There is thus room for improvements in this technical field.

[0012] BRIEF DESCRIPTION OF INVENTION

[0013] The aim of the present application is to improve the design and functionality of a safety lancet this aim is obtained by a safety lancet according to the features of the independent patent claim. Preferable embodiments of the safety lancet form the subject of the dependent patent claims.

[0015] According to one aspect, a safety lancet is provided comprising a lancet body provided with a support surface to be in contact with a penetration site when in use, wherein the support surface is arranged with a passage, a hinge mechanism arranged to the lancet body, a carrier comprising a penetration element and connected to the hinge mechanism and being linearly movable along a first axis between a first position with the penetration element inside the lancet body and a second position with the penetration element protruding through the passage, an elongated flexible actuator connected with one end to the lancet body extending in a proximal direction and with a free end resting on a flexible force element positioned adjacent the hinge mechanism in the first position, and an activator operably connected to the actuator, which activator is manually movable in a direction along a second axis generally perpendicular to the first axis.

[0017] In operation, a manual movement of the activator in the direction of the second axis will cause the free end of the flexible actuator to move along the force element and to bias the force element such that the actuator is pushed in the distal direction, building up a force in the actuator, until the manual movement of the activator will push the free end of the actuator off the force element, wherein the free end of the actuator will hit the hinge mechanism and, by the force of the actuator, move the carrier and the penetration element rapidly in a proximal direction to the second position and perform a penetration.

[0019] With this solution, the penetration force is created by the flexible force element of the lancet body. Thus, no additional metal springs or the like are needed, which provides a cost-effective yet well-functioning solution. Because of the build-up of the bending force and the sudden release of the actuator, which in turn hits the carrier, the penetration movement is very rapid, in the order of milli-seconds, whereby the pain or discomfort experienced by the patient is reduced.

[0021] According to a further aspect, the hinge mechanism may be biased in a distal direction in the first position and wherein further manual movement of the activator may move the actuator out of contact with the hinge mechanism, in turn causing the carrier and penetration element to move back to the first position.

[0023] This is also advantageous because the penetration element is quickly retracted after the penetration due to the biasing properties of the hinge mechanism and that the actuator releases the hinge mechanism very shortly after the penetration. Moreover, the retraction of the carrier and the penetration element into the safety lancet body reduces the risk of accidental contact with the penetration element and thus reduced risk of blood contamination.

[0025] In order to ascertain a proper and predictable penetration by the penetration element, the lancet body may further comprise a guide surface generally parallel with the first axis, and wherein a side surface of the carrier may be moved in contact with the guide surface for guiding the carrier along the first axis during penetration.

[0027] As a further positive feature regarding the penetration speed, also a bending force may be built up in the actuator during the movement along the force element. Thus, forces are built up both in the actuator and in the force element. In this regard, the force element may comprise a flexible tongue.

[0029] In order to further reduce the risk of accidental contact with the penetration element, the safety lancet may further comprise a first locking element arranged on the actuator and a second locking element arranged on the lancet body, cooperating to lock the actuator after the actuator has been moved out of contact with the hinge mechanism.

[0031] Regarding the build-up of bending force in the actuator, the activator or the actuator may further comprise a support element, which support element may be arranged to be in contact with the actuator or the activator during the movement and bending of the actuator. In this regard, the support element may comprise an arc-shaped contact surface.

[0032] These and other aspects of, and advantages with, the present invention will become apparent from the following detailed description of the invention and from the accompanying drawings.

[0034] BRIEF DESCRIPTION OF DRAWINGS

[0035] In the following detailed description of the invention, reference will be made to the accompanying drawings, of which

[0037] Fig. 1 is a perspective view of a first embodiment of a safety lancet,

[0039] Figs. 2-5 are side views of the safety lancet of Fig. 1 in different operational positions,

[0041] Figs. 6-7 are side views of a second embodiment of a safety lancet, and

[0043] Figs. 8-9 are side views of a third embodiment of a safety lancet.

[0045] DETAILED DESCRIPTION OF THE INVENTION

[0046] In the following detailed description, certain words related to directions will be used, that are defined in the following. The word proximal means at or towards a penetration site of a patient or user, while the word distal is the opposite direction. The word upper relates to an orientation of the safety lancet when in normal use, while the word lower is the opposite orientation. The word outer relates to an outside of the safety lancet and the word inner relates to the interior of the safety lancet.

[0048] A safety lancet 10 shown in the drawings comprises a lancet body 12. The lancet body 12 comprises a proximal contact element 14 having an arc-shaped contact surface. A central passage 16 is provided in the contact element 14. Integrated with the contact element 14 is a first wall or portion 18 extending in the distal direction. An upper and outer area of the first portion 18 is provided with grip-enhancing elements 20, like ribs as shown in the drawings. The first portion 18 transforms into an upper, generally arc-shaped portion 22. At the transition between the first portion 18 and the upper portion 22, a material reduction 24 is arranged, providing a living hinge as will be explained below. The upper portion 22 then transforms into a second wall portion 26 extending in the proximal direction with a free end, which is provided with an outwardly extending protrusion or tongue 27, which will function as a first locking element as will be described. The second portion 26 will hereafter be referred to as activator. An outer area of the activator 26 is also provided with grip-enhancing elements 28. From the contact element 14 a third portion 30 is extending distally, towards the activator 26. The portions 18, 26 described above have a width that provides a good grip and handling of the safety lancet as seen in Fig. 1.

[0050] To an inner surface of the third portion 30, a hinge mechanism 32 is attached or integrated. The hinge mechanism 32 comprises a first hinge section 34 in the form of an arm extending from an inner surface of the third portion 30 distally and inclined in relation to a first axis X1, which axis extends proximally-distally. The first hinge section 34 may have a material reduction 36 at the connection with the third portion 30, providing a living hinge function. To the inner end of the first hinge section 34, a second hinge section 38 is provided, extending proximally and also inclined in relation to the first axis X1. Moreover, the first hinge section 34 extends somewhat further inwards, creating a first locking protrusion 39, as will be described below. To the free end of the second hinge section 38, a carrier 40 is provided. The carrier 40 in turn is provided with a penetration element 42, Fig. 3, such as a pointed needle as shown, or a blade, extending proximally from the carrier 40 and provided with a pointed end. Initially, the penetration element 42 is covered and kept sterile by a shield 43. The carrier 40 is provided with a straight side surface 44 with an orientation generally coinciding with the direction of the first axis X1. Moreover, an inner area of the third portion 30 adjacent the carrier 40 is also provided with a straight guide surface 46 with the same orientation.

[0052] Distally of the first hinge section 34, a force element 48 is extending from the inner surface of the third portion 30 with generally the same inclination as the first hinge section 34. The force element 48 is in the form of a flexible tongue. Further, an actuator 50 in the form of an elongated flexible arm extends proximally from a transition area between the upper portion 22 and the activator 26, and inwardly of the activator 26. The actuator 50 has a free end 52 provided with a second locking protrusion extending in the distal direction and inclined in relation to the axis X1. The free end 52 of the actuator 50 is positioned distally of and adjacent the attachment point between the force element 48 and the third portion 30 in an initial, nonactivated, state of the safety lancet. The activator 26 may further be provided with a support element 54 on an inner surface thereof. In the embodiment shown in Figs. 1-5, the support element is in the form of an elongated protrusion provided with an arcshaped edge facing the actuator 50.

[0054] The safety lancet is intended to be used as follows. When delivered to a user, be it a patient or medical staff, the orientation and position of the above described components are as shown in Fig. 2. At delivery, the penetration element 42 is protected by the shield 43, providing sterility to the penetration element 42 before use. When the safety device is to be used, the shield 43 is removed, Fig. 3, and the contact element 14 is placed against a penetration site, preferably the tip of a finger, where the user holds the safety lancet 10 at the upper areas provided with the grip enhancing elements 20 and 28. Due to the arc-shape of the contact surface of the contact element 14, a correct penetration position is obtained. The user now presses the activator 26 inwards along a second axis X2 in a direction generally perpendicular to the first axis X1. This causes the arc-shaped surface of the support element 54 to come in contact with the actuator 50, causing a bending action of the actuator 50. Further movement will cause the free end 52 of the actuator 50 to move inwards along the distal surface of the force element 48, Fig. 3, which in turn will bias proximally and create a bending force in the force element 48.

[0056] This bending force will act on the actuator 50 and force it to move distally, aided by the living hinge 24 between the first portion 18 and the upper portion 22. Moreover, this will also cause the build-up of a bending force in the actuator 50, in particular from the support element 54. Thus, forces are built up in the actuator 50 of the safety lancet 10. Further movement will now cause the free end 52 of the actuator 50 to suddenly leave the force element 48, releasing the actuator 50. Because of the forces built up, the actuator 50 with its free end 52 will rapidly move in the proximal direction and hit the first hinge section 34, Fig. 4, which in turn will cause the hinge mechanism 32 to move the carrier 40 rapidly proximally and cause a penetration by the tip of the penetration element 42. During this proximal movement, the side surface 44 of the carrier 40 and the guide surface 46 of the third portion 30 will guide the carrier 40 in a straight proximal direction during the penetration, ascertaining a correct penetration direction of the penetration element 42 along the first axis X1. Further, due to the actuator 50 acting on the hinge mechanism in a cam-like manner as seen in Fig. 4, a precise and consistent penetration depth is obtained regardless of thickness of the patient’s skin at the penetration site.

[0058] As the actuator 50 is moved further inwards during the operation, its free 52 end will be moved out of contact with the first hinge section 34 of the hinge mechanism 32, Fig. 5, and due to it biasing properties in the distal direction, the carrier with 40 its penetration element 42 will be moved distally away from the penetration site and into the safety lancet, preventing any accidental contact and possible injury when the safety lancet is removed. In order to further reduce the risk of accidental contact, the tongue 27 of the activator 26 will pass the free end of the force element 48 and when the grip of a user is released, the activator 26 will be biased outwardly whereby the tongue 27 will be positioned proximally of the force element 48, which now functions as a second locking element. The activator 26 is thereby locked in the transversal direction along axis X2, as well as the actuator 50, which is locked between the support element 54 and the inner wall of the first portion 18, as seen in Fig. 5.

[0059] Further, the second locking protrusion 52 now engages with the first locking protrusion 39 to hold the carrier 40 in the retracted position. Thereby, no manipulation can be made in order to move the carrier 40 again, whereby the penetration element 42 is safe within the safety lancet. In order to further prevent manipulation and/or re-use of the safety lancet the material thickness of the living hinge 24 between the first portion 18 and the upper portion 22, as well as the type of material may be chosen such that it will break if further attempts to manipulate the safety lancet are done after it has been used and is locked.

[0061] Another embodiment of the safety lancet is shown in Figs. 6 and 7. Most of the components and their functions are the same as the previous embodiment and will not be discussed further. Flowever, this embodiment is provided with a support element 60 provided on the actuator 50 positioned somewhat half way between the attachment end and the free end. The support element 60 may be a protrusion or tongue extending towards an inner surface of the activator 26. Moreover, the actuator 50 may be provided with a first locking element 62 that is to cooperate with a second locking element 64 provided on an inner surface of the first portion 18. In the embodiment shown the first and second locking elements 62, 64 are in the form of protruding tabs that can engage with each other. Thus, when the actuator 50 has been pressed inwards so that its free end has passed the hinge mechanism 32 and the carrier 40 and penetration element 42 are retracted as described above, Fig. 7, the first and second locking elements 62, 64 engage with each other to lock the actuator 50. Thereby, the actuator 50 cannot be moved or forced back to act on the hinge mechanism 32 after completed operation. As a further safety measure, the living hinge 24 between the first portion 18 and the upper portion 22 may be designed such that any further manipulation of the safety lancet will cause the living hinge 24 to break, rendering the safety lancet useless for further use.

[0063] A third embodiment is shown in Figs. 8 and 9. Most of the components and their functions are the same as the previous embodiment and will not be discussed further. However, this embodiment has no support element but is provided with an activator 26 with a lower part angled outwardly so as to form a distinct inwardly directed contact point 70. When the activator 26 is operated as described above, the contact point 70 will come in contact with the actuator 50 and cause a bending action as seen in Fig. 9.

[0065] The safety lancet according to the invention is preferably made in one piece of a plastic material such as for example POM. Preferably the safety lancet is produced by injection moulding. In this regard, the needle may be held in one half of the cavity by a magnet if two cavities are used.

[0067] It is to be understood that the embodiments described above and shown in the drawings are to be regarded as non-limiting examples of the invention and that it may be modified in many ways within the scope of the patent claims.

Claims

1. A safety lancet (10) comprising

- a lancet body (12) provided with a contact element (14) provided with a contact surface for being in contact with a penetration site in use, the contact element (14) being provided with a passage (16),

- a hinge mechanism (32) arranged at the lancet body (12),

- a carrier (40) comprising a penetration element (42) and connected to the hinge mechanism (32) and which is linearly movable along a first axis (X1) between a first position with the penetration element inside the lancet body and a second position with the penetration element (42) protruding through the passage (16),

- an elongated flexible actuator (50) connected with one end to the lancet body (12) extending in a proximal direction and with a free end (52) resting on a flexible force member (48) positioned adjacent the hinge mechanism (32) in the first position,

- an actuator (26) operabably connected to the actuator (50), said actuator (26) being manually movable in a direction along a second axis (X2) substantially perpendicular to the first axis (X1).

that the activator (26) or actuator (50) further comprises a support element or a contact point (54, 60, 70),

wherein manual movement of the actuator (26) in the direction of the second axis (X2) will cause the free end (52) of the flexible actuator (50) to move along the force member (48) and bias the force member (48) such that the flexible actuator (50) is bent and pushed in the distal direction by the support member or contact point (54, 60, 70) that is in contact with the actuator (26) or actuator (50) during the movement of the actuator (50), which builds up a bending force in the actuator (50), until the manual movement of the actuator (26) will push the free end (52) of the actuator (50) away from the force member (48), whereby the free end (52) of the actuator (50) will strike the hinge mechanism (32) and, by the bending force of the actuator, move the carrier (40) and the penetration element (42) rapidly in the proximal direction to the second position and perform a penetration.

2. A safety lancet according to claim 1, wherein the hinge mechanism (32) is biased distally in the first position and wherein further manual movement of the actuator (26) will move the actuator (50) out of contact with the hinge mechanism (32), which in turn causes the carrier (40) and the penetration element (42) to move back to the first position.

3. A safety lancet according to claim 1 or 2, wherein the lancet body (12) further comprises a guide surface (46) generally parallel to the first axis (X1), and wherein a side surface (44) of the carrier (40) moves into contact with the guide surface (46) to guide the carrier (40) along the first axis (X1) during penetration.

A safety lancet according to any preceding claim, wherein the force element (48) comprises a flexible tongue.

5. A safety lancet according to any one of the preceding claims, further comprising a first locking element (27, 62) arranged at the activator (26) or actuator (50) and a second locking element (48, 64) arranged at the lancet body, which cooperate to lock the actuator (50) after the actuator (50) has been moved out of contact with the hinge mechanism.

6. The safety lancet of claim 1, wherein the support element (54) comprises an arcuate contact surface.