The invention refers to a blood removal system for withdrawing blood for diagnostic purposes.
In order to withdraw a minimal amount of blood from body parts (generally, a finger or an ear lobe) for analytical-diagnostic purposes, lancets are used, which are pricked into the corresponding body part for producing a wound. Because this procedure is manually performed, specially trained personnel are necessary. However, the puncture is connected with substantial pain.
Blood removal systems which comprise a pricking apparatus and associated lancets, specially adapted to the lancets, have also been used. In a housing of the pricking apparatus, a lancet drive is located, by means of which a lancet is mechanically stuck into the skin. A spring serves as a driving element for the puncturing movement. At the beginning of the development, very simple constructions were used, in which the lancet was directly attached to an end of a compression spring arranged in an elongated housing (for example, U.S. Pat. No. 4,469,110).
These types of blood removal system were, however, not suitable to meet the high demands required when a routine monitoring of analytical values of blood is necessary. This is particularly true for diabetics, who must control their blood sugar levels frequently, in order to maintain their blood sugar levels as constant as possible within predetermined nominal limits by means of adapting insulin injections to the requirements (which, depending on the nutrient absorption, the bodily activity, etc., can vary strongly). By comprehensive scientific research, it was demonstrated that by means of an intensive therapy with at least four blood analyses per day, a dramatic decrease of the most severe consequences of diabetes mellitus (for example, a retinal pathology with resulting blindness of the patient) can be achieved.
This intensive therapy requires that the blood removal is connected with the least possible pain. Numerous different blood removal systems were developed with the aim to achieve this goal.
A blood removal with very little pain is achieved by blood removal systems, whose lancet drive includes a drive rotor, which on one side (the input side) is coupled with the drive spring in such a manner that it can be driven thereby to rotate about an axis of rotation. On the other side (output side) it is coupled via a coupling mechanism with the lancet, in such a manner that the rotation of the drive rotor resulting from the tension releasing movement of the drive spring is converted to a puncturing movement whereby the lancet is moved with high speed, until its point or tip exits from the exit opening, thereby producing a wound in the body part which is pressed against a contact surface surrounding the exit opening. The lancet is guided by a lancet guide on a predetermined (in practice, straight) puncture path.
A blood lancet device with such a rotor drive is described in U.S. Pat. No. 4,924,879. Its rotor is driven by means of a coaxial helical spring. The rotational movement of the rotor is converted into the required linear movement of the lancet via a con-rod drive.
In U.S. Pat. No. 5,318,584, a blood removal system is described, which, likewise, operates with a rotor drive. The drive rotor of this system rotates about an axis of rotation, which coincides with the axis of the longitudinally extending, “pencil-shaped” apparatus. A rotational spring that is coaxial with the rotor serves as the drive. The output-side coupling mechanism for converting the rotational movement into the translation movement of the lancet is formed by a curve controller. The form of the control curve makes it possible to cock the apparatus, without the lancet tip exiting from the housing. The rotation of the rotor part about the longitudinal axis of the apparatus leads to very little vibration and stabilizes the puncturing process. A newer version of a blood removal system with a drive rotor that rotates about the apparatus longitudinal axis is described in EP 1034740 A1.
A further embodiment of a rotor drive is described in EP 1090584 A2, in which a drive rotor is used, which rotates about an axis that runs transverse to the direction of puncture. Here the rotation of the drive rotor is caused by the force of the drive spring pressing against a specially formed pressure surface of the rotor. In this manner, it is possible that the rotor rotates in the same direction of rotation both during cocking as well as upon tension release of the lancet drive. Also in this case, the output-side coupling mechanism preferably comprises a curve controller. The construction requires fewer components than the previously discussed rotor drive. It requires, however, a relatively wide housing shape, which is considered less favorable by many users.
In spite of the extensive development work, which has led to the previously discussed and numerous further designs, a large interest exists in a blood removal system, which, at the same time, fulfills, to the extent possible, the difficult and partially opposing requirements (minimal pain, simple operation, compact, most slim structure, and simple, cost-effective construction).
To fulfill these requirements, the present invention is based on a blood removal system with a rotor drive. In this respect, in particular with regard to the required output-side coupling mechanism for conversion of the rotational movement of the drive rotor into the translation movement of the lancet, reference is made to the previously discussed documents. The disclosure of these documents is incorporated herein by reference. Based on this basic design the present invention proposes that the end of the drive spring facing away from the drive rotor is connected to a rotatably moveable cocking element, the cocking element is rotatable for tensioning of the drive spring, with inhibited rotation of the drive rotor, in the same direction of rotation in which the drive rotor rotates during the driving phase and that the cocking element is arrested during the drive phase against a backward rotation, so that the drive rotor, after releasing the rotation inhibition, performs a rotational movement, which, by means of the output-side coupling mechanism, is converted into the puncturing movement of the lancet.
With the earlier known rotor drives it was general practice that the drive spring (and thereby the entire rotor drive) was brought into the cocked state by turning the drive rotor backwards (i.e., in a rotation direction contrary to its direction during the puncturing movement). EP 1090584 A2 shows an exception, in which the specially formed pressure surface has alternating driving sections and tensioning sections in such a manner that the drive spring is tensioned via unidirectional rotation of the drive rotor when in the tensioning phase of the rotor drive, it is in contact with the tensioning section of the pressure surface, while in the driving phase of the drive the spring is in contact with a driving section of the rotor, whereby the rotational movement is driven by the relaxing spring.
According to the invention, the rotationally moveable cocking element and the drive rotor are alternately rotated in the same direction of rotation:
This principle is subsequently designated as “One Way Alternating Drive and Cocking”, or OWADAC.
In one embodiment of the invention, the drive spring is connected directly, without further intermediary components, on one side to the drive rotor, and on the other side, directly to the cocking element. This configuration may require fewer components and provide reduced friction, in particular, when, according to another embodiment of the present invention, the axis of rotation of the cocking element runs coaxial to the axis of rotation of the drive rotor. In principle, it is also possible that the rotational axes of the cocking element and the drive rotor are parallel, but not coaxial, or that they even run at an angle to one another that is different from 0°. In this case, in particular, the connection of the drive spring relative to the drive rotor and/or the cocking element may be indirect, that is, further components (for example, gears or other drive parts) are provided, which permit the required conversion of the flow of force. Thus the statement that the spring is “connected to” or “supported against” the cocking element and the drive rotor is to be understood in the general sense that a force transfer between the cocking element, the drive spring and the drive rotor is provided, by means of which the rotation of the cocking element with a fixed drive rotor leads to tensioning of the drive spring and, with a fixed cocking element, the de-tensioning of the previously biased spring drives the drive rotor while the cocking element is fixed.
The invention will be described hereafter in greater detail with reference to the embodiments shown in the figures. The characteristics shown therein can be used individually or in combination, to provide preferred embodiments of the invention. In the figures:
a-2e are partially fragmented, perspective views of a blood removal system according to the present invention in five different movement positions or phases of the lancet drive.
The embodiments described below are merely exemplary and are not intended to limit the invention to the precise forms disclosed. Instead, the embodiments were selected for description to enable one of ordinary skill in the art to practice the invention.
The blood removal system 1 shown in
The revolver head 4 is rotatable about an axis of rotation B to be positioned in a plurality of positions, in which, respectively, one lancet 3 is arranged coaxial with the main axis A of the puncture apparatus 2. The lancet bodies 8 and the recesses 9, in which the lancets 3 sit, are shaped relative to one another such that the walls of the recesses 9 form lancet guides 10, by means of which the respective lancet 3 is guided on a predetermined puncture path (here, along the main axis A).
In the housing 6 of the puncture apparatus 2, a lancet drive 12 is provided, which serves to move a lancet 3 with high speed in the puncturing direction 13, until its tip 14 protrudes from an exit opening 15, while the puncture apparatus 2 is pressed with a contact surface 16 surrounding the exit opening 15 against a body part (not shown). Thereby, a wound for removal of blood is produced in the body part.
Before the puncturing movement is initiated a respective lancet 3 must be coupled with the lancet drive 12. In the shown embodiment this is achieved by means of a connecting rod, designated as a pushrod 18. On the end of the pushrod 18 facing the lancet 3, a holding element 19 with larger cross-section is provided, which for coupling of a lancet is inserted into a corresponding holding device 20 of the lancet body 8. The holding device 20 is formed, such that it engages the holding element 19 of the pushrod 18 in cooperation with the shape of the recess 9, when the pushrod 18 is moved so far in the puncturing direction 13 that its front end contacts the lancet body and displaces the lancet 3 from the position shown in
In the embodiment shown, the lancet 3 is “directly guided”, that is, it is located directly in a part of the housing 6 (in the present case, a magazine which contains a plurality of lancets) that forms the guide required during the puncturing movement. The embodiment of the lancet drive explained here is suited in particular for such directly guided, magazined lancets. However, it is also usable with the generally used indirect lancet guides, where the lancet drive is permanently coupled with a lancet holder, into which a new lancet is manually inserted for each blood withdrawal. During the puncture process, the lancet holder is guided by means of a housing part serving as a guide and thereby indirectly provides the required guide of the lancet on the puncturing path. This type of construction is described in the earlier publications cited above.
The lancet drive 12 comprises essentially a drive spring 22, a cocking device 23 for tensioning of the drive spring 22, and a drive rotor 24 that is driven by the drive spring 22 and is rotatable about axis A. The drive rotor 24 is secured against axial displacement by means of a bearing pin 21. By means of an output-side coupling mechanism 25, the rotational movement of the drive rotor 24 is converted into the puncturing movement which is by means of the pushrod 18 transferred to a lancet coupled thereon.
The output-side coupling mechanism 25 is in the shown device embodied as a curve controller with a control curve 27 and a control pin 28 travelling along the control curve 27 during the puncturing movement. In the shown embodiment, the control curve 27 is formed by a recess running about the periphery of the drive rotor 24. The control pin 28 is formed on a driving sleeve 30, which surrounds the part of the drive rotor 24 provided with the control curve 27. The driving sleeve 30 is non-rotatably guided by means of a longitudinal groove (not shown), such that it can only carry out a translation movement. At its front end, the pushrod 18 is rigidly fixed. The output-side coupling mechanism 25 is similar to the curve controllers described in U.S. Pat. No. 5,318,584 and in EP 1034740 A1. In the present invention, however, the drive rotor need not be reversely rotated during the tensioning of the drive spring 22. Therefore, on the one hand, a very simple form of the control curve 27 can be chosen, and on the other hand, the entire angle of rotation of 360° can be used for the conversion of the rotational movement of the drive rotor 24 into a translation movement of the pushrod 18 and a lancet 3 connected therewith.
This is achieved in that the cocking device 23 is designed according to the OWADAC principle. The end of the drive spring 22 facing away from the drive rotor 24 is connected to a rotationally movable cocking element 33, which, for tensioning of the drive spring 22 is rotatable in the same direction, in which the drive rotor 24 rotates during the driving phase, while the rotation of the drive rotor 24 is inhibited. During the driving phase, the cocking element 33 is arrested against a reverse rotation, so that the drive rotor 24, after release of its rotation-inhibiting state, performs the rotational movement. This again is converted into the puncturing movement of the lancet 3.
With the embodiment shown in
Certain functions of the lancet drive 12 can be more clearly recognized with reference to
The movement position in
When the locking cam 42 is pivoted by means of an actuator element (not shown), into the position shown in
The movement of the lancet drive in the preparation angle of rotation range can be used for preparation of the actual puncture process. In particular, it can serve to couple the lancet drive with a lancet stored in a magazine. In particular, the coupling mechanism shown in
During the cocking phase shown in
The driving phase of the lancet drive 12 shown in
e shows the position of the maximum penetration of the lancet 3, which corresponds with the lower reversal point of control curve 27. At the end of the puncture- and return movement, the rotational movement is stopped by the forward locking catch 44 of the locking cam 42, and the lancet drive is in the base state (
In the initial section of the preparation angle of rotation range 51, the slope of the control curve 27 is small. This causes a slow movement with relative strong force. In the position P1 (in the case shown, at a puncture depth of 1 mm and an angle of 30°), a protective film covering the lancet receiving recesses 9 at the rear of the revolver head 4 is pierced by means of the front end of the pushrod 18 (
The axis of the drive rotor runs parallel to the puncture direction (as shown in
Such an embodiment of a blood removal system 1 is shown in
For cocking of the lancet drive 12, a translatory moving actuator element 36 is moved in the puncture direction by means of an actuator button 56. A gear rod 57 is a component of actuator element 36 and drives a pinion 58 that is coaxial to the cocking element 33. Pinion 58 is connected with cocking element 33 via a free wheel 59 (
By means of the rotation of the cocking element 33, the drive spring 22 is tensioned. In this embodiment, the drive spring 22 is formed as a spiral spring and is located in a recess 64 of the rotatably moveable cocking element 33 facing the drive rotor 24.
In this embodiment, the output-side coupling mechanism 25 again includes a control curve 27, which is formed by a recess 29 in drive rotor 24. The control curve 27 has, in the case shown, the shape of a circle eccentric to the axis C. During rotation of the drive rotor 24 a control pin 28 (
The rear end of lancet holder 65 with control pin 28 engages in a circumferential gap of the drive module 55 in such a manner that rotational movement of the components of module 55 is not hindered. To this end the shown embodiment comprises a separating disc 68 made, for example, of metal, which lies on a plateau of the drive rotor 24 in such a manner that the circumferential gap remains. It has a width required for accommodating the lancet holder 65 between disc 68 and the parts of the rotor 24 that are radially outward from control curve 27.
In this embodiment, the cocking- and puncture movement again includes the phases explained with reference to
Based on the preceding description, numerous alternative embodiments of the invention are apparent to a person skilled in the art. For example, the following modifications can be made:
The foregoing description of the invention is illustrative only, and is not intended to limit the scope of the invention to the precise terms set forth. Although the invention has been described in detail with reference to certain illustrative embodiments, variations and modifications exist within the scope and spirit of the invention as described and defined in the following claims.
Number | Date | Country | Kind |
---|---|---|---|
102 23 558 | May 2002 | DE | national |
Number | Name | Date | Kind |
---|---|---|---|
3030959 | Grunert | Apr 1962 | A |
3244317 | Raybin | Apr 1966 | A |
3696915 | Douglas | Oct 1972 | A |
3833146 | Braginetz | Sep 1974 | A |
4139011 | Benoit et al. | Feb 1979 | A |
4203446 | Höfert et al. | May 1980 | A |
4388925 | Burns | Jun 1983 | A |
4416279 | Lindner et al. | Nov 1983 | A |
4442836 | Meinecke et al. | Apr 1984 | A |
4449529 | Burns et al. | May 1984 | A |
4469110 | Slama | Sep 1984 | A |
4527561 | Burns | Jul 1985 | A |
4535769 | Burns | Aug 1985 | A |
4539988 | Shirley et al. | Sep 1985 | A |
4553541 | Burns | Nov 1985 | A |
4577630 | Nitzsche et al. | Mar 1986 | A |
4624253 | Burns | Nov 1986 | A |
4635633 | Hufnagle | Jan 1987 | A |
4653513 | Dombrowski | Mar 1987 | A |
4677979 | Burns | Jul 1987 | A |
4712548 | Enstrom | Dec 1987 | A |
4715374 | Maggio | Dec 1987 | A |
4735203 | Ryder et al. | Apr 1988 | A |
4738261 | Enstrom | Apr 1988 | A |
4794926 | Munsch et al. | Jan 1989 | A |
4817603 | Turner et al. | Apr 1989 | A |
4821878 | Jones | Apr 1989 | A |
4844095 | Chiodo et al. | Jul 1989 | A |
4856515 | Turner et al. | Aug 1989 | A |
4858607 | Jordan et al. | Aug 1989 | A |
4860937 | Arnold | Aug 1989 | A |
4869249 | Crossman et al. | Sep 1989 | A |
4889117 | Stevens | Dec 1989 | A |
4892097 | Ranalletta et al. | Jan 1990 | A |
4895147 | Bodicky et al. | Jan 1990 | A |
4924879 | O'Brien | May 1990 | A |
4976724 | Nieto et al. | Dec 1990 | A |
4983178 | Schnell | Jan 1991 | A |
4990154 | Brown et al. | Feb 1991 | A |
4994068 | Hufnagle | Feb 1991 | A |
4995402 | Smith et al. | Feb 1991 | A |
4998452 | Blum | Mar 1991 | A |
5026388 | Ingalz | Jun 1991 | A |
5029583 | Meserol et al. | Jul 1991 | A |
5035704 | Lambert et al. | Jul 1991 | A |
5047044 | Smith et al. | Sep 1991 | A |
5070886 | Mitchen et al. | Dec 1991 | A |
5074872 | Brown et al. | Dec 1991 | A |
5100427 | Crossman et al. | Mar 1992 | A |
5100428 | Mumford | Mar 1992 | A |
5105823 | Blum | Apr 1992 | A |
5120311 | Sagstetter et al. | Jun 1992 | A |
5133730 | Biro et al. | Jul 1992 | A |
5147375 | Sullivan et al. | Sep 1992 | A |
5152775 | Ruppert | Oct 1992 | A |
5196025 | Ranalleta et al. | Mar 1993 | A |
5207699 | Coe | May 1993 | A |
5269800 | Davis, Jr. | Dec 1993 | A |
5304192 | Crouse | Apr 1994 | A |
5304193 | Zhadanov | Apr 1994 | A |
5314442 | Morita | May 1994 | A |
5318584 | Lange et al. | Jun 1994 | A |
5356420 | Czernecki et al. | Oct 1994 | A |
5366470 | Ramel | Nov 1994 | A |
5397334 | Schenk et al. | Mar 1995 | A |
5439473 | Jorgensen | Aug 1995 | A |
5464418 | Schraga | Nov 1995 | A |
5478345 | Stone et al. | Dec 1995 | A |
5487748 | Marshall et al. | Jan 1996 | A |
5514152 | Smith | May 1996 | A |
5527334 | Kanner et al. | Jun 1996 | A |
5531763 | Mastri et al. | Jul 1996 | A |
5554166 | Lange et al. | Sep 1996 | A |
5628765 | Morita | May 1997 | A |
5632410 | Moulton et al. | May 1997 | A |
5636640 | Staehlin | Jun 1997 | A |
5643306 | Schraga | Jul 1997 | A |
5662669 | Abidin et al. | Sep 1997 | A |
5755733 | Morita | May 1998 | A |
5829589 | Nguyen et al. | Nov 1998 | A |
5908434 | Schraga | Jun 1999 | A |
5951582 | Thorne et al. | Sep 1999 | A |
5984940 | Davis et al. | Nov 1999 | A |
6056765 | Bajaj et al. | May 2000 | A |
6109740 | Namekawa et al. | Aug 2000 | A |
6358265 | Thorne, Jr. et al. | Mar 2002 | B1 |
6409740 | Kuhr et al. | Jun 2002 | B1 |
6419661 | Kuhr et al. | Jul 2002 | B1 |
6472220 | Simons et al. | Oct 2002 | B1 |
6514270 | Schraga | Feb 2003 | B1 |
6719771 | Crossman | Apr 2004 | B1 |
20030050656 | Schraga | Mar 2003 | A1 |
20040039407 | Schraga | Feb 2004 | A1 |
20040127928 | Whitson et al. | Jul 2004 | A1 |
20050090850 | Thoes et al. | Apr 2005 | A1 |
20050131441 | Iio et al. | Jun 2005 | A1 |
Number | Date | Country |
---|---|---|
2 803 345 | Jun 1979 | DE |
38 42 317 | Jun 1990 | DE |
G 92 05 278.9 | Aug 1992 | DE |
0 036 443 | Mar 1986 | EP |
0 081 665 | Apr 1986 | EP |
0 204 892 | Jan 1991 | EP |
0 178 384 | Nov 1991 | EP |
0 199 484 | Mar 1993 | EP |
0 565 970 | Oct 1993 | EP |
0 589 186 | Mar 1994 | EP |
0 582 226 | Oct 1997 | EP |
0 931 507 | Jul 1999 | EP |
2 508 305 | Dec 1982 | FR |
1085141 | Sep 1967 | GB |
2002143131 | May 2002 | JP |
WO 8504089 | Sep 1985 | WO |
WO 9300044 | Jan 1993 | WO |
WO 9602189 | Feb 1996 | WO |
WO 9814125 | Apr 1998 | WO |
WO 0100090 | Jan 2001 | WO |
WO 0236010 | May 2002 | WO |
Number | Date | Country | |
---|---|---|---|
20040092996 A1 | May 2004 | US |