DE102004064136B4 - Lancet device for making puncture wound for taking out body fluid for diagnostic purpose has reference element coupling mechanism with lancet drive for moving reference element and cam which is driven by cam rider - Google Patents

Abstract

Lancet device has housing in which lancet is movable in puncturing way and lancet drive (9) with drive spring which is driven by drive rotor (12) and lancet coupling mechanism for converting rotating motion of drive rotor into puncturing and return motion of lancet. Reference element coupling mechanism (38) with lancet drive moves reference element (14) and cam (33) is driven by cam rider (34). An independent claim is also included for lancet drive building group for lancet device.

Description

The invention relates to a lancet device for creating a puncture wound, in particular for removing blood for diagnostic purposes, and a lancet drive assembly for a lancet device.

In order to remove a small amount of blood from a body part (usually from a finger or earlobe) for analytic-diagnostic purposes, lancets are used, which are pierced into the corresponding body part to produce a puncture wound. As far as this is done manually, specially trained personnel is required. Nevertheless, the puncture is associated with considerable pain.

Blood collection systems have long been used which consist of a lancet device and associated lancets specially adapted to the particular lancet device. In a housing of the lancet device is a lancet drive, through which a lancet is mechanically pricked into the skin. The drive element for the puncturing movement is a spring. At the beginning of the development, very simple constructions were used, in which the lancet was attached directly to one end of a compression spring arranged in an elongated housing (eg. U.S. Patent 4,469,110 ).

However, such blood collection systems have failed to meet the high requirements that must be met when periodic monitoring of analytical blood levels is required. This is especially true for diabetics, who should often control their blood sugar levels to keep them within certain limits by insulin injections. Extensive scientific research has shown that intensive therapy with at least four blood analyzes a day can dramatically reduce severe late damage to diabetic mellitus (such as retinopathy resulting in blindness to the patient).

This intensive therapy requires that the blood collection is associated with the least possible pain. With the aim of achieving an improvement in this regard, numerous different blood collection systems have been developed.

Low-pain blood sampling allow lancet devices whose lancet drive includes a drive rotor, on the one hand (drive side), the drive spring acts such that it can be offset by this in a rotational movement about an axis of rotation, and on the other hand via a (output side) coupling mechanism so with the lancet is coupled, that the resulting from the relaxation movement of the drive spring rotation of the drive rotor is converted into a puncturing movement. The present invention preferably relates to a lancing device with such a rotor-lancet drive, which is known in various embodiments.

The output-side coupling mechanism is typically designed so that the lancet is coupled to the drive rotor during the entire insertion and return movement (drive phase of movement of the lancet drive) and thereby the lancet movement is completely controlled by the corresponding movement of the drive rotor. An early example of such a design shows that U.S. Patent 4,924,879 , More modern embodiments are for example in the U.S. Patents 6409740 and 6419661 described.

The clamping of the known rotor lancet drives is generally carried out in that the rotor is rotated back by means of a suitable "drive-side coupling mechanism" against the force of the drive spring. Recently, a construction has become known in which an additional tensioning rotor is used for tensioning the drive spring. As a result, it can be achieved that the clamping of the lancet drive takes place in a clamping phase of its movement by a rotation of the clamping rotor, which is rectified with the rotation of the drive rotor in the drive phase. This drive principle is also referred to as OWADAC (one way alternating drive and cocking). Such a rotor drive is for example in the EP 1384438 A1 described.

In the EP 1405595 A1 and in the US 2004/0127818 lancet devices are described in which a reproducible puncture depth is sought by means of an auxiliary or reference element, which is moved together with the lancet in the direction of the skin during the puncturing movement. After the puncture of the lancet into the skin, a contact surface of the auxiliary or reference element strikes the skin or a stop fixed to the housing and thereby limits the stitch depth.

Despite extensive development work, there continues to be great interest in a lancet device that at the same time as far as possible meets the difficult and sometimes contradictory requirements (minimal sensation of pain, simple operability, compact design, cost-effective design). Another requirement is that the lancet device is not contaminated during use or as little as possible by escaping blood. The object of the invention is to fulfill these requirements as far as possible.

This object is achieved by a lancet device for producing a puncture wound in a skin surface, in particular for removing blood for diagnostic purposes, comprising a housing in which a lancet is movable on a puncture path, a lancet drive for driving a puncture and return movement on the puncture path, a relative to the lancet and relative to the housing movable reference element which is fixed during the piercing movement in a defined position relative to the lancet drive (and thus to the puncture path) and rests with a contact surface on the skin surface, so that by the puncturing movement a puncture and a reference element coupling mechanism coupled to move the reference element with the lancet drive, the reference element being moved away from the puncture wound after puncture, before being soiled by leaking blood d.

In order to obtain sufficient blood for diagnostic purposes with the least painful puncture possible, the optimal penetration depth is of central importance. Variations of 0.05 mm may result in a significant change in the sensation of pain and / or the amount of blood collected during a puncture.

In lancet devices with a rotor-lancet drive, the movement of the lancet, as described, is precisely controlled by the coupling with the drive rotor. The puncture depth corresponds to the distance between the lowest point (reversal point) of the lancet movement and the level of a skin contact surface, which surrounds an opening at the front end of the housing in known constructions as an annular pressure surface. The pressure surface is pressed against the body part from which blood is to be taken. To adjust the penetration depth, its axial position (that is, the position in the puncture direction) is adjustable.

If the opening surrounded by the pressure surface is only slightly larger than the lancet diameter, the penetration depth is well reproducible, but the amount of blood obtained by a puncture is relatively small and, in particular, for integrated systems in which a blood sample is to be evaluated in the lancet device sufficient. If the housing opening surrounded by the pressure surface is larger, so that the skin bulges into it, a larger amount of blood can be obtained with a puncture because of an increased blood flow.

In the context of the invention it has been found that with a trained as a pressure surface at the front end of the housing skin contact surface no optimal reproducibility of the penetration depth can be achieved as soon as the skin bulges when pressing a lancet device in the surrounded by the pressure surface housing opening, since the inner edge then represents only an inaccurate reference for the penetration depth. For smaller case openings, this effect is less pronounced, but less blood is then recovered and there is an increased risk that the lancet device will be contaminated by blood leaking from the puncture wound.

So far, attempts have been made to solve this problem, the best possible compromise for the inner diameter of the pressure surface, d. H. the size of the housing opening, to find. In contrast to this conventional procedure, a lancet device according to the invention has a reference element (movable relative to the lancet and the housing) which rests on the skin of a patient during the puncture with a contact surface. To move the reference element is a reference element coupling mechanism, which is provided in addition to the lancet coupling mechanism. The movable reference element is fixed during the piercing movement in a defined position relative to the lancet drive. It is clear from the following description that with such a construction a very good reproducibility of the depth of the puncture wound despite vaulting of the skin can be achieved.

The reference element of a lancet device according to the invention may be designed as a sample receiving unit, which has a guide channel for the lancet and a sample receiving channel for receiving a blood sample next to one another. From the sample receiving unit, the blood sample can be forwarded to another processing station (for example, to analyze it). Preferably, however, a reaction zone with reagents is an integral part of the sample receiving unit, so that the sample receiving unit forms a complete analysis element. The reaction of the sample with the reagents in the reaction zone results in a change in a physical state (for example, a color change or in electrochemical analysis elements to alter a current flow) that can be used as the basis for determining the concentration of an analyte contained in the sample. Since such analysis elements are known, a more detailed explanation of the test principles is not required. The analysis elements (or other sample receiving units) are disposed of after a single use. Therefore, contamination by blood leaving the puncture wound plays no role.

Since the mouth of the sample collection channel through which the sample is taken, is spatially separated from the mouth of the guide channel, after the puncture, the sample receiving unit must be moved so that the mouth of the sample collection channel is brought to the puncture wound for a sample recording. This is done by the reference element coupling mechanism, which is provided in addition to the lancet coupling mechanism. Although it is in principle also possible to use the mouth of the lancet guide channel for the sample receiving channel, so that the channels are not spatially separated and the described movement is not necessary. In the context of the invention, however, it has been found that it is better to provide separate channels and, for example by a pivoting movement to bring the mouth of the sample receiving channel after the puncture to the puncture wound.

The invention relates in particular to cases in which the reference element is a reusable component of the lancet device. In this case, contamination of the reference element by exiting from the puncture wound blood is of course undesirable. It is therefore according to the invention after the puncture quickly moved away from the puncture wound before it is contaminated by escaping blood.

In the context of the invention, it was found that the contact pressure with which the reference element is pressed against the skin during a puncture counteracted the escape of blood from the puncture wound. This finding is exploited by removing the reference element from the puncture wound by a sufficiently rapid motion before blood can leak out and contaminate the reference element (to an annoying degree).

Preferably, the reference element is moved away within 50 milliseconds after the puncture at least 2 mm from the puncture wound. To drive such a fast return movement of the reference element, in particular, the drive rotor of the lancet drive is suitable. For a painless puncture, the lancet must be moved at high speed. The reference element coupling mechanism therefore preferably converts a rotary movement of the drive rotor into a movement of the reference element, which preferably extends in a translatory manner.

An important component of the lancet device according to the invention is a lancet drive assembly comprising a lancet drive with a drivable by a drive spring drive rotor and a tensioning rotor for tensioning the drive spring, a first lancet coupling mechanism for converting a rotational movement of the drive rotor in a puncture and return movement of the lancet and a another coupled with the lancet drive coupling mechanism.

The further coupling mechanism is preferably used for moving a reference element, but can also be used, for example, in an analyzer with integrated lancet device for further indexing a magazine with test strips, for applying an antiseptic to the puncture site or for receiving a sample on a test field.

The invention will be explained in more detail with reference to embodiments shown in FIGS. The features illustrated therein may be used alone or in combination to provide preferred embodiments. Identical or corresponding components are identified by matching reference numerals. Show it:

1 a perspective view of a lancet device;

2 a perspective view of a lancing device with removed housing;

2a a schematic detail cross-sectional view of in 2 shown lancet device;

3 a perspective view of a lancet drive assembly with a drum magazine;

4 another perspective view of the in the 2 and 3 shown embodiment;

5 a graphic representation of the movement of the lancet and the reference element in the assembly of 3 depending on the angular position of the drive rotor;

6 a perspective view of another embodiment of a lancet drive assembly;

7 a graphic representation of the movement of the lancet and the reference element in the assembly of 6 depending on the angular position of the clamping rotor;

8th a perspective view of another embodiment of a lancet drive assembly;

9 a perspective, exploded view of the parts of in 8th shown embodiment; and

10 a schematic representation of a reference element in the form of a sample receiving unit.

In the 1 shown lancet device 1 is used to create a puncture wound to remove blood for diagnostic purposes. Your housing 2 has a housing opening 3 on, through which the tip of a lancet, in the case 2 is movable on a puncture, exits to produce a puncture wound in a part of the body located in front of the housing opening.

The housing opening 3 is of an annular pressure surface 6 surrounded with the lancet device for a puncture against a body part, for example, a fingertip, is pressed. The skin surface bulges into the housing opening 3 into it. The protrusion of the skin facilitates blood leakage, so that even with a comparatively small penetration depth of 0.5 mm to 2 mm, a sufficient amount of blood can be removed for diagnostic purposes. By repeatedly pressing against the skin, this effect can be additionally improved ("pumping action"). In addition, with a blood collection device designed in this way, a blood drop can also be taken from less well-perfused but also less sensitive to pain, parts of the body. To ensure the desired pumping action, the inner diameter of the pressure surface should 6 be quite large, preferably at least 7 to 9 mm.

The pressure surface is preferred 6 inside to the housing opening 3 inclined towards. In particular, it is advantageous, the pressure surface 6 from a deformable material, such as polyurethane or rubber, to form, which can be the said pumping effect when pressed against a body part still strengthen. Further details and alternative embodiments of the pressure surface 6 are in the DE 100 26 172 A1 described in this regard by reference is made to the subject of the present application. The pressure surface is formed there by a component which is referred to as a compression unit because of its pumping action.

The construction described results in that the exact position of the skin surface relative to the lancing device depends on the contact pressure and other factors (for example the tension of the skin) and is not exactly defined. Based on 2 and 3 will be explained below, how it can nevertheless be ensured that during the puncturing movement of the lancet, a puncture wound with a predetermined puncture depth is generated.

2 shows the lancet device 1 with removed housing, 3 their lancet drive assembly 10 that with a drum magazine 16 connected is. The assembly 10 includes a drive rotor 12 which is drivable by a drive spring, and a tensioning rotor 13 for tensioning the drive spring. For better clarity, the drive spring between the drive rotor 12 and the tensioning rotor 13 is arranged in the 2 and 3 not shown. The drive spring 11 is only in 4 to see. It is a torsion spring, which is biased and with one end to the drive rotor 12 and with its other end to the tension rotor 13 is articulated.

Another component of the lancet drive assembly 10 is a driven-side lancet coupling mechanism 24 , By the rotational movement of the rotatable about an axis drive rotor 12 is converted into a puncture movement in a drive phase of the lancet drive, in which the lancet is moved at high speed in the puncture direction to produce a puncture wound. Also, the return movement of the lancet is by the rotational movement of the drive rotor 12 by means of the lancet coupling mechanism 24 driven and controlled. During the entire drive phase (which includes the puncture and return movement) is supported by the drive rotor 12 facing away from the end of the drive spring against the clamping rotor, which is locked in the drive phase such that it can not be reversed (against the direction of rotation of the drive rotor) can be rotated. In a clamping phase of the lancet drive movement of the tensioning rotor for tensioning the drive spring with inhibited rotation of the drive rotor 12 rotatable in the same direction of rotation, in which the drive rotor 12 during the drive phase rotates. Such a lancet drive is in the EP 1384438 A1 whose contents, in particular with regard to the details of the lancet drive, are incorporated by reference into the subject of the present application.

The lancet driver assembly 10 further comprises another coupling mechanism 38 in which a rotational movement of a rotating component of the lancet drive into a movement of the reference element 14 or another component of a lancet device can be implemented. Because this further coupling mechanism 38 in the described embodiment for moving the reference element 14 serves, it is referred to in this context as a reference element coupling mechanism.

The reference member is movable relative to the lancet and relative to the housing. It is designed and arranged so that during a puncturing movement of the lancet with its contact surface in a defined position relative to the Lancet drive on the skin surface of a patient rests. This ensures that a puncture wound is produced with a predetermined puncture depth, which corresponds to the distance between the contact surface of the reference element and the lowest position of the lancet tip in the puncture direction.

At the in 2 embodiment shown, the reference element closes 14 a drum magazine 16 , in which several lancets can be stored, and one the drum magazine 16 surrounding protective cap 17 one. The contact surface 15 is on a protective cap 17 formed, with which the reference element 14 rests against the skin surface. As in particular the schematic representation of the front part of the reference element 14 in 2a shows is in the contact area 15 a lancet opening 18 formed, through which the lancet emerges at a puncture, in a against the housing opening 3 (ie against the pressure surface 6 ) pressed fingers to create a puncture wound. In 4 is the reference element 14 with removed protective cap 17 and its connection to the reference element coupling mechanism 38 shown.

For sterile storage of lancets until their use, it is preferred if the drum magazine 16 has several chambers, in each of which a single lancet is stored. But it is also possible, the lancets ring in a drum magazine 16 to arrange, which is not divided into individual chambers. The number of in a drum magazine 16 stored lancets is largely arbitrary. Preferably summarizes a drum magazine 16 three to twelve, more preferably four to eight lancets. The drum magazine 16 is relative to the lancet opening 18 the protective cap 17 so rotatable that outlet openings 20 the drum magazine 16 in turn for a puncture in alignment with the lancet opening 18 are positionable.

To the lancet coupling mechanism 24 includes a non-rotatably connected to the housing thrust cylinder 25 from which a coupling rod 26 which is connected during the puncture and return movement with one ("active") lancet. The lancet coupling mechanism 24 sets the rotational movement of the drive rotor 12 by means of a cam control in a translational movement of the active lancet.

For this purpose, the thrust cylinder 25 provided with a recess in the form of a groove having a control cam 27 forms and of a cam rider 28 of the drive rotor 12 is traversed. In the embodiment shown, the cam rider 28 formed as a control pin which engages in the groove and at the end of one of the drive rotor 12 outgoing control arm 29 sitting. The push cylinder 25 is with guide elements 32 provided in the axially extending longitudinal grooves in the inner wall of the housing 2 (not shown) engage to a non-rotatable, but in the piercing direction movable connection of the push cylinder 25 in the case 2 to reach. In the embodiment shown, the guide elements 32 realized as two guide pin.

The following with reference to the 3 and 4 described reference element coupling mechanism 38 with which after a puncture the reference element 14 withdrawn from the puncture wound also works with a curve control. Your control curve 33 is from a recess in the form of a groove in the drive rotor 12 formed into which a cam rider 34 engages in the form of a control pin. He is over a coupling arm 35 with a guide rod 36 connected to the drum magazine 16 is attached. The coupling arm 35 carries the reference element 14 , The guide rod 36 is opposite the coupling arm 35 rotatable, so over the guide rod 36 the drum magazine 16 in the reference element 14 can be rotated, and in this way the in the drum magazine 16 stored lancets can be used in turn.

The distance between the drum magazine is adjusted to adjust the puncture depth 16 and the contact surface 15 forming protective cap 17 changed by the length of the reference element 14 is adjusted by a thread (not shown). The setting is made via the in 2 shown wave 19 that have a gear 21 with a sprocket 22 of the reference element 14 is engaged.

To tension the drive spring is the tension rotor 13 via a gearbox 37 that is preferred by a battery-powered electric motor 40 ( 2 ) is driven, set in rotation. The tension rotor 13 but also by means of a from the housing 2 outstanding shaft to be turned by hand.

To the spring force of the drive spring 11 To be able to use as efficiently as possible for a rapid puncture and return movement, it has proved to be advantageous if preparatory movements of the lancet and the reference element 14 be carried out before the tensioning or at the latest during the tensioning of the drive spring.

For this reason, pass through the drive rotor 12 and the tensioning rotor 13 First, in a preparation phase, a preparation rotation angle range, before the drive spring is tensioned. This is a rotational movement of the clamping rotor 13 over the preloaded drive spring so on the drive rotor 12 transmit that during at least part of the preparation phase together (ie, simultaneously, but not necessarily, but preferably, synchronously) with the tensioning rotor 13 is turned. One of the coupling mechanisms is the movement of the drive rotor 12 in the preparation rotation angle range in a preparatory movement of the coupling rod 26 relative to the drum magazine 16 implemented, in which the coupling rod 26 through a lancet opening 18 opposite insertion opening (not shown) in a chamber of the drum magazine 16 penetrates and rusted with a lancet contained therein. Further details and alternative embodiments of a suitable coupling mechanism are disclosed in U.S. Patent Nos. 5,436,074 WO 02/36010 A1 described in this regard by reference is made to the subject of the present application.

While the drive rotor 12 and the tensioning rotor 13 go through the preparation rotation angle range, by the reference element coupling mechanism 38 the reference element 14 in the case 2 so far in the direction of its housing opening 3 advanced that with the contact surface 15 can rest against the skin of a patient. Due to the size of the inner diameter of the pressure surface 6 the fingertip bulges when creating something in the housing opening 3 of the lancet device 1 ( 1 ) into it. The reference element 14 can therefore with its contact surface 15 lie against the skin, although it is in the case 2 located in a position where the contact surface 15 by far behind you through the inner edge 7 the pressure surface 6 extending level runs.

If the drive rotor 12 has passed through the preparatory rotation angle range, it is by means of a blocking element 41 locked so that during the subsequent clamping phase of the lancet drive movement upon further rotation of the drive rotor 13 the drive spring is tensioned. In the embodiment shown, the blocking element 41 as resilient on an inner wall of the housing 2 adjacent triggering tongue formed by the drive rotor 12 goes out and for locking the drive rotor 12 engages in a recess in the inner wall of the housing. The release tab is integral with the control arm 42 of the control pin 28 manufactured as an injection molded part.

Is the drive rotor 12 through the blocking element 41 locked, so leads to a further rotational movement of the clamping rotor 13 for tensioning the drive spring. At the tension rotor 13 There are electrical contacts (not shown) for switching off the electric motor 40 which are closed when the tension rotor 13 has passed through a predetermined Spanndrehwinkelbereich. This completes the cocking phase. Will the tension rotor 13 driven by hand, so it can be blocked after passing through the Spanndrehwinkelbereichs by a mechanical locking.

A puncturing movement is initiated by a completed clamping process in that the blocking element 41 is released from its blockade engagement, so that in the drive phase of the drive rotor 12 , driven by the drive spring, very quickly turns into its rest position. It turns in the same direction as the tensioning rotor 13 when tensioning the drive spring. This fast movement of the drive rotor 12 is via the lancet coupling mechanism 24 in a puncture and return movement of the lancet and the reference element coupling mechanism 38 in a return movement of the reference element 14 implemented.

During the return movement of the reference element 14 it is just as in the return movement of the lancet to a translational movement in the axial direction. This ensures that the rapid movement of the drive rotor 12 both for the return movement of the reference element 14 As well as being used for the return movement of the lancet, one can achieve that the reference element 14 removed so quickly from the puncture wound that it is practically not contaminated by leaking blood.

The puncturing process can be triggered (triggered), for example, by the contact surface 15 of the reference element 14 is pressed against the skin with a predetermined minimum force. Preferably, the reference element 14 a pressure sensor with which a signal required to trigger a puncturing movement can be generated as soon as the contact surface 15 a pressure is exerted that exceeds a predetermined Mindestanpreßdruck. The pressure sensor can be realized, for example, in that the contact surface 15 is mounted on a spring and an electrical contact is closed only after compression of the spring.

Alternatively or additionally, a release button 5 on the housing 2 the lancet device 1 be arranged ( 1 ). To trigger the puncturing process, an electrical signal is initially generated in the illustrated embodiment, through which the electric motor 40 is set in motion. This will make the tension rotor 13 rotated by a small angle of rotation. How to get in 3 sees, the tension rotor points 13 a release cam 44 on, the rotation of the clamping rotor 13 beyond a predetermined angular position beyond a trigger mechanism 45 operated by the previously existing inhibition of the drive rotor 12 is solved.

In the embodiment shown, the triggering mechanism 45 formed as a rocker, which is around journals 46 pivotable on the housing 2 is attached. Through the release cam 44 of the tension rotor 13 becomes an end of the seesaw 45 raised and the other end of the rocker 45 on which there is a headboard 47 is lowered. The blocking element 41 has a shoulder with a return surface 48 on. In this (in 3 not shown) movement phase is the head part 47 above the blocking element 41 and press on the return surface 48 the trigger tongue 41 , whereby these from their engagement with the recess of the housing 3 is solved. Once the blocking element 41 the drive rotor 12 no longer blocked, the drive spring relaxes, so that the drive phase of the movement of the lancet drive expires.

5 illustrates which movements of the lancet and the reference element 14 by the rotational movement of the drive rotor 12 by means of the coupling mechanisms 24 . 38 be driven and controlled. In 5 is the stroke, so the movement in the axial direction, the coupling rod 26 as curve A and the stroke of the reference element 14 as a curve B over the rotational angle position of the drive rotor 12 applied. Shown is a complete cycle of operation of the lancet drive, which includes a rotational movement of the drive rotor by a total of 360 °. A work cycle begins with the beginning of a rotary movement of the tensioning rotor and ends with the end of the return movement of the lancet after the puncture.

At the beginning of the working cycle, the drive rotor passes through 12 (as set forth above in a relatively slow movement simultaneously with the tensioning rotor) preparatory rotation angle range γ. It ends at about 120 ° (in 5 indicated by a vertical line). The movement of the drive rotor 12 in the preparation rotation angle range is by means of the two coupling mechanisms 24 . 38 implemented so that both the coupling rod 26 as well as the reference element 14 in the device forward (towards the housing opening 3 towards) until the contact surface 15 of the reference element 14 on the skin and the coupling rod 26 is coupled to a lancet.

Because the contact surface 15 At the time of the puncture, the depth of the puncture wound is precisely defined by the section Δh of the coupling rod stroke, which is above the contact surface 15 goes. After the puncture, the coupling rod 26 and the reference element 14 withdrawn to their initial positions. The drive rotation angle range (which corresponds to the drive phase of the lancet drive movement, consisting of puncture and return motion), which follows the preparation rotation angle range, is traversed in less than 100 ms, preferably less than 20 ms.

6 shows a further embodiment of a lancet drive assembly 10 , It is without the reference element 14 shown, so the head 50 the guide rod 36 on which the drum magazine 16 is attached, and the coupling rod 26 , which are locked for a puncture with a lancet, can be seen better. It can also be seen that the coupling rod end 49 has a thickening, which allows a positive coupling to a lancet. As with the basis of the 2 and 3 described embodiment, the between the drive rotor 12 and the tensioning rotor 13 arranged drive spring not shown.

In 6 it can be seen that the drive rotor 12 and the tensioning rotor 13 stop parts 51 have, in a stop position of the rotors 12 . 13 abutting one another and thereby a rotational movement of the drive rotor 12 relative to the tensioning rotor 13 to stop. Such stop parts 51 are also present in the embodiment described above. They serve in particular to receive the bias of the drive spring and at the end of the puncture and return movement the drive rotor 12 to stop.

As already mentioned, in the preparation rotational angle range, a rotational movement of the tensioning rotor 13 over the drive spring 11 on the drive rotor 12 transferred so that the tensioning rotor 13 and the drive rotor 12 rotate together in the preparation rotation angle range. By the bias of the drive spring 11 becomes a tight coupling of the tensioning rotor 13 with the drive rotor 12 achieved, so that the angular position of the clamping rotor 13 during the common rotation of the rotational angular position of the drive rotor at most by 10 °, preferably at most by 5 °, deviates. A sufficiently high bias of the drive spring 11 is used in this way to achieve a largely synchronous, so angular and speed-true movement of the two rotors. This has the advantage that the movements of the coupling mechanisms 24 . 38 can be controlled even more precise. Alternatively, a synchronous movement of the two rotors can be 12 . 13 also by coupling them together while passing through the preparatory rotation angle range by a locking bar (not shown).

Also in further details, this embodiment corresponds largely to the basis of the 2 to 4 described embodiment. In particular, there is a difference in that with the reference element coupling mechanism 38 a rotational movement of the tensioning rotor 13 (not the drive rotor) in a movement of the reference element 14 is implemented. Therefore, in the embodiment shown, the control cam 33 the reference element coupling mechanism 38 (Also as a groove-shaped recess) in the tensioning rotor 13 educated. The reference element coupling mechanism 38 is not in this design for a fast return movement of the reference element 14 used after a puncture, but for a precise adjustment of the penetration depth by a slow movement of the reference element 14 , As 5 illustrated, the penetration depth depends on the position in which the contact surface 15 of the reference element 14 relative to the coupling rod 26 is located when the puncture movement is triggered. To set the penetration depth, the reference element 14 before a puncture relative to the coupling rod 26 moved in the axial direction. This adjustment movement takes place independently of the puncturing movement and can be carried out slowly. The set position must not change during the puncture movement. Therefore, for this purpose, the reference element coupling mechanism 38 preferably with the tensioning rotor 13 coupled, which rotates relatively slowly.

In 7 is the movement of the coupling rod 26 and thus also the lancet as curve C as well as the movement of the reference element 14 as a curve D as a function of the angular position of the clamping rotor 13 shown.

Preferably, the adjustment of the penetration depth after the clamping operation. A first section of the control curve 33 the reference element coupling mechanism serves to the reference element 14 first to move to a maximum position M, which corresponds to a minimum penetration depth. Will the tension rotor 13 then further rotated, so is the reference element 14 from this maximum position M moves back to a position corresponding to the desired penetration depth ("puncture position"). The further the reference element 14 relative to the coupling rod 26 is retracted, the greater the depth of the subsequent puncture. Once the puncture position has been reached with the desired penetration depth, the electric motor becomes 40 switched off and the tensioning rotor 13 locked in this position. After release, the tensioning rotor ends 13 its working cycle by being further rotated in the movement section Q until it reaches its starting position.

In the described procedure for adjusting the penetration depth, it is of great importance that the rotational angle position of the tensioning rotor 13 is locked exactly in the desired position. An inaccurate positioning of the angular position of the clamping rotor 13 leads to a corresponding inaccuracy in the set penetration depth. In the embodiment shown, the electric motor drives 40 the tensioning rotor 13 via a two-stage worm gear 37 on, so that the rotational angle position of the tensioning rotor 13 by electronically counting the revolutions of one or more parts of the worm gear 37 can be adjusted precisely.

The embodiments of the 2 to 4 and 6 can be combined so that a first reference element coupling mechanism is the reference element 14 with the tensioning rotor 13 coupled to set the penetration depth before triggering a puncturing movement, and a second reference element coupling mechanism, the reference element 14 with the drive rotor 12 coupled to after a puncture the reference element 14 to move. In this way, the drive spring is used for a fast return movement, which is due to an electric motor 40 would be very difficult to realize while the electric motor 40 is used for a slow adjustment movement of the penetration depth, for which the drive spring is less suitable.

The 8th and 9 show a further embodiment of a lancet drive assembly 10 , In contrast to the embodiments described so far, the reference element is in this embodiment 14 as sample receiving unit 60 educated. As in 10 can be seen more clearly contains the sample receiving unit 60 a guide channel 61 for the lancet 4 and a sample receiving channel 63 with a mouth 63a to record a sample. The sample receiving unit 60 also has a reaction zone 64 with reagents on which the sample passes through the sample collection channel 63 can be fed.

As with the other embodiments, the lancet driver assembly includes 10 one by a drive spring 11 drivable drive rotor 12 that's about an axis 59 is rotatable, and a tensioning rotor 13 for tensioning the drive spring 11 , drive rotor 12 and tensioning rotor 13 are arranged coaxially. In the in the 8th and 9 illustrated embodiment is the drive spring 11 a torsion spring designed as a helical spring. Alternatively, for example, a coil spring as a drive spring 11 possible.

The turns of the drive spring 11 may be wound at a distance to minimize frictional losses, or closely abutted to dampen torsional vibrations, with tension in the pulling direction providing damping friction between the turns.

To the bias of the drive spring 11 to pick up, the tension rotor indicates 13 a stop member in the form of a stop groove 52 in, in the one stop pin 53 of the drive rotor 12 intervenes. The stop pin 53 is caused by the bias of the drive spring 11 against one end of the arcuate stopper groove 52 pressed to which he strikes in a resting position.

After a puncture, an estuary 63a ( 10 ) of the sample receiving channel 63 brought to the created puncture wound to allow the uptake of the blood sample exiting the wound.

For this purpose, the reference element coupling mechanism comprises 38 one around two journals 69 swiveling suspended sleeve 65 with a rigid control arm 66 , with a control pin as a cam rider 67 in a cam formed by a groove-shaped recess 68 of the drive rotor 12 intervenes. The control curve 68 has two semicircular sections with different radii. Moves the cam rider 67 between these two sections, this causes a pivotal movement of the sleeve 65 , In the sleeve 65 is the coupling rod 70 the lancet coupling mechanism 24 translationally movable to the puncture and return movement of the lancet 4 to enable. The coupling rod 70 is from the drive rotor 12 over a connecting rod 71 driven. The connecting rod 71 carries a crank pin 72 into a hole 75 of the drive rotor 12 intervenes.

So that blood emerging from the puncture wound as completely as possible from the sample receiving channel 63 the sample receiving unit 60 is received in the embodiment shown, a second reference element coupling mechanism 39 provided after the puncturing the sample receiving unit 60 pulls something back and pushes forward after the pivoting movement so that a drop of blood from the sample receiving channel 63 can be included.

The second reference element coupling mechanism 39 includes a sleeve 77 from which a rigid control arm 78 with a control pin as a cam rider 79 goes out, in a formed by a groove-shaped cam 73 of the drive rotor 12 intervenes. In the embodiment shown, the control cam 68 on a first side (front) of the drive rotor 12 and the control curve 73 arranged on its back. The sleeve 77 is around the coupling rod 70 around and in the pod 65 of the first reference element coupling mechanism 38 arranged.

A complete cycle of work in the 8th and 9 illustrated lancing device runs as follows:
The lancet device is attached to a body part of a patient, so that the contact surface 15 of the sample receiving unit 16 formed reference element 14 rests against the skin surface. For tensioning the drive spring 11 becomes the tensioning rotor 13 rotated by 180 ° while the drive rotor 12 by a locking element (not shown) is held. To trigger the puncture, the locking element (not shown) is released, so that the drive rotor 12 performs a snap movement of 180 ° until the stop pin 53 against the end of the stop 52 of the tension rotor 53 encounters.

During this movement of the drive rotor 12 describes the crank pin 72 the lower half of a circular path, so that by means of the connecting rod 71 and the coupling rod 70 the lancet coupling mechanism 24 the puncture movement of the lancet 4 is performed. On the last section of the snap action of the drive rotor 12 causes the second reference element coupling mechanism 39 over the control curve 73 that the sleeve 77 and the sample receiving unit held therein 60 is withdrawn. Now the contact surface 15 no longer on the skin surface, blood can escape.

By the engine 40 then the tensioning rotor 13 moved again by 180 °, with the drive rotor 12 because of the bias of the drive spring 11 this 180 ° movement follows. By the shape of the control curve 68 it comes to a pivoting movement of the sleeve 65 that is sized to the mouth 63a ( 10 ) of the sample receiving unit 60 is aligned to the puncture site. The groove 73 causes it over the connecting rod 71 and the coupling rod 70 the sample receiving unit 60 pushed back to the front, leaving the mouth 63a comes in contact with escaped blood and absorbs it.

Instead of the crankpin 72 and the connecting rod 71 also a third groove in the drive rotor can be used to connect via a third cam rider the coupling rod 70 drive.

To improve blood leakage may additionally with a pressure piece, for example, the lower edge of the sleeve 77 , be acted upon the skin surface in the vicinity of the puncture site. By pressing such a pressure piece, blood can be squeezed out of the puncture wound coming from the sample receiving unit 60 can be included. If the contact force is lowered after blood collection has been completed, then the puncture wound closes. Further details on the support of blood collection by a pressure piece are in the European patent application EP 04008691.0 which is hereby incorporated by reference in the present application.

The sample receiving unit 60 is additionally with a pump tappet 76 ( 10 ) to capillary forces of the sample collection channel 63 to reinforce by suction. The sample receiving unit 60 is with struts 80 provided that relax after the puncture and the pump plunger 76 pull back so that blood enters the sample collection channel 63 is sucked.

With suitable design of the cams 68 and 73 or the coupling mechanisms 38 . 39 can be in support of the blood collection also realize a pumping motion, for example by tension rotor 13 and drive rotor 12 be moved forwards and backwards over a small angle range. Is the bias of the drive spring 11 so big that the tension rotor 12 and the drive rotor 13 move substantially synchronously, in particular whose angular position differs from each other at most by 10 °, in addition to forward movements and backward movements in precise control of the movements are possible.

LIST OF REFERENCE NUMBERS

1

Lancet device

2

casing

3

housing opening

4

lancet

5

release button

6

pressure surface

7

edge

8th

finger receiving

10

Lancet drive assembly

11

driving spring

12

drive rotor

13

tensioning rotor

14

reference element

15

contact area

16

drum magazine

17

protective cap

18

Lancet opening

19

wave

20

outlet opening

21

gear

22

sprocket

24

Lancet coupling mechanism

25

push cylinder

26

coupling rod

27

cam

28

Control curve

29

control arm

32

guide elements

33

cam

34

Control curve

35

coupling arm

36

guide rod

37

transmission

38

Reference element coupling mechanism

39

Reference element coupling mechanism

40

electric motor

41

blocking element

44

release cam

45

trigger mechanism

46

pivot

47

headboard

48

Return surface

49

Coupling rod end

50

head

51

stop parts

52

stopper

53

stop pin

59

axis

60

Sample receiving unit

61

guide channel

63

Sample-receiving channel

63a

muzzle

64

reaction zone

65

shell

66

control arm

67

Control curve

68

cam

69

pivot

70

coupling rod

71

connecting rod

72

crank pin

73

cam

75

drilling

76

pump plunger

77

shell

78

control arm

79

Control curve

80

strut

Claims (20)

A lancet device for creating a puncture wound in a skin surface, in particular for removing blood for diagnostic purposes, comprising: a housing ( 2 ), in which a lancet ( 4 ) is movable on a puncture path, a lancet drive ( 9 ) for driving a puncturing movement of a via a lancet coupling mechanism ( 24 ) with the lancet drive ( 9 ) coupled lancet ( 4 ) on the puncture path, a reference element ( 14 ), which relative to the housing ( 2 ) is movable during the puncture movement in a defined position relative to the lancet drive ( 9 ) and thus fixed to the puncture path and with a contact surface ( 15 ) abuts the skin surface, so that a puncture wound with reproducible penetration depth is generated by the puncturing movement, and a reference element coupling mechanism ( 38 . 39 ), which in addition to the lancet coupling mechanism ( 24 ) and to move the Reference element ( 14 ) with the lancet drive ( 9 ), wherein the reference element is moved away from the puncture wound after the puncture, before it is contaminated by escaping blood. Lancet device according to claim 1, in which the reference element ( 14 ) is moved away from the puncture wound at least 2 mm within 50 milliseconds after the puncture. Lancet device according to one of the preceding claims, in which the movement of the reference element ( 14 ) away from the puncture wound by the rotational movement of a drive rotor ( 12 ) via a lancet coupling mechanism ( 24 ) also with the lancet ( 4 ) is coupled. Lancet device according to claim 3, in which the reference element coupling mechanism ( 38 . 39 ) a Drehwegung the drive rotor ( 12 ) in the movement of the reference element ( 14 ). Lancet device according to claim 4, in which the movement of the reference element ( 14 ) is a translational movement. Lancet device according to one of the preceding claims, in which the reference element ( 14 ) is formed as a sample receiving unit having a guide channel for the lancet and a sample receiving channel for receiving a blood sample. The lancing device of claim 6, wherein the sample receiving unit includes a reaction zone with reagents. Lancet device according to claim 7, characterized in that the reaction zone ( 64 ) with the sample receiving channel ( 63 ) is connected in such a way that in the sample receiving channel ( 63 ) received blood to the reaction zone ( 64 ) is transported. Lancet device according to claim 8, characterized in that the sample receiving unit ( 63 ) by means of the reference element coupling mechanism ( 38 ) is moved such that a sample receiving opening of the sample receiving channel ( 63 ) is brought to the puncture wound for receiving a sample. Lancet device according to claim 9, characterized in that the movement of the sample receiving unit ( 63 ) includes a pivoting movement. Lancet device according to one of claims 3 to 10, characterized in that the lancet drive ( 9 ) a tensioning rotor ( 13 ) for tensioning a drive spring ( 11 ). Lancet device according to claim 11, characterized in that the drive rotor ( 12 ) in a work cycle undergoes a total rotation angle range comprising a preparation rotation angle range in which the drive rotor ( 12 ) together with the tensioning rotor ( 13 ) turns. Lancet device according to claim 12, characterized in that the lancet coupling mechanism ( 24 ) a coupling rod ( 26 ), which attaches to the lancet ( 4 ) is coupled while the drive rotor ( 12 ) goes through the preparation rotation angle range. Lancet device according to one of claims 11 to 13, characterized in that the tensioning rotor ( 13 ) a release cam ( 44 ), which upon rotation of the tensioning rotor ( 13 ) beyond a predetermined angular position, a triggering mechanism ( 45 ) actuated by the triggering of a puncturing movement, a locking of the drive rotor ( 12 ) is solved. Lancet device according to one of claims 11 to 15, characterized in that it comprises an electric motor ( 40 ) for tensioning the drive spring ( 11 ) having. Lancet device according to one of the preceding claims, characterized in that the reference element ( 14 ) has a pressure sensor with which a signal required for triggering a puncturing movement is generated as soon as the contact area ( 15 ) acts a pressure exceeding a predetermined Mindestanpreßdruck. Lancet device according to one of the preceding claims, characterized in that the reference element coupling mechanism has a control cam ( 27 . 33 ), which by a cam rider ( 28 . 34 ) is traversed. Lancet device according to one of claims 11 to 17, characterized in that a first reference element coupling mechanism ( 38 ) the reference element ( 14 ) with the tensioning rotor ( 13 ), preferably to adjust a penetration depth prior to the initiation of a puncture motion, and a second reference element coupling mechanism (US Pat. 39 ) the reference element ( 14 ) with the drive rotor ( 12 ) coupled to the reference element ( 14 ) after a puncture from the puncture wound. Lancet device according to one of the preceding claims, characterized in that the reference element ( 14 ) in the housing ( 2 ) is arranged at a distance to a plane passing through the inner edge ( 7 ) a pressure surface ( 6 ), with which the lancet device is pressed against a body part from which blood is to be withdrawn. Lancet device according to one of the preceding claims, characterized in that the reference element ( 14 ) a magazine ( 16 ), in which several lancets ( 4 ) are storable.

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